• Cisco Talos discovered a new threat actor we’re calling “CoralRaider” that we believe is of Vietnamese origin and financially motivated. CoralRaider has been operating since at least 2023, targeting victims in several Asian and Southeast Asian countries. 
• This group focuses on stealing victims’ credentials, financial data, and social media accounts, including business and advertisement accounts.
• They use RotBot, a customized variant of QuasarRAT, and XClient stealer as payloads in the campaign we analyzed.
• The actor uses the dead drop technique, abusing a legitimate service to host the C2 configuration file and uncommon living-off-the-land binaries (LoLBins), including Windows Forfiles.exe and FoDHelper.exe 

CoralRaider operators likely based in Vietnam 

Talos assesses with high confidence that the CoralRaider operators are based in Vietnam, based on the actor messages in their Telegram C2 bot channels and language preference in naming their bots, PDB strings, and other Vietnamese words hardcoded in their payload binaries. The actor’s IP address is located in Hanoi, Vietnam. 

 Our analysis revealed that the actor uses a Telegram bot, as a C2, to exfiltrate the victim’s data. This allowed us to collect information and uncover several invaluable indicators about the origin and activities of the attacker. 

The attacker used two Telegram bots: A “debug” bot for debugging, and an “online” bot where victim data was received. However, a Desktop image in the “debug” bot had a similar desktop and Telegram to the “online” bot. This showed that the actor possibly infected their own environment while testing the bot. 

Analyzing the images of the actor’s Desktop on the Telegram bot, we found a few Telegram groups in Vietnamese named “Kiém tien tử Facebook,” “Mua Bán Scan MINI,” and “Mua Bán Scan Meta.” Monitoring these groups revealed that they were underground markets where, among other activities, victim data was traded. 

In an image from the “debug bot,” we spotted the Windows device ID (HWID) and an IP address (118[.]71[.]64[.]18), located in Hanoi, Vietnam, that is likely to be CoralRaider’s IP address.

Talos’ research uncovered two other images that revealed a few folders on their OneDrive. One of the folders had a Vietnamese name, “Bot Export Chiến,” which is the same as one of the folders in the PDB strings of their loader component. Pivoting on the folder path in the PDB string, we discovered a few other PDB strings having similar paths but different Vietnamese names. We analyzed the discovered samples with the PDB strings and found they belong to the same loader family, RotBot. The Vietnamese name in the PDB string of the loader binary further strengthens our assessment that CoralRaider is of Vietnamese origin.

Another image we analyzed is an Excel spreadsheet that likely contained the victims’ data. We have redacted the images to maintain confidentiality. The spreadsheet has several tabs in Vietnamese, and their English translation showed us the tabs “Employee salary spreadsheet,” “advertising costs,” “website to buy copies,” “PayPal related,” and “can use.” The spreadsheet seemed to have multiple versions — the first was created on May 10, 2023. We also spotted that they have logged into their Microsoft Office 365 account with the display name “daloia krag” while accessing the spreadsheet, and CoralRaider likely operates the account. 

CoralRaider’s payload, XClient stealer analysis, showed us a few more indicators. CoralRaider had hardcoded Vietnamese words in several stealer functions of their payload XClient stealer. The stealer function maps the stolen victim’s information to hardcoded Vietnamese words and writes them to a text file on the victim machine’s temporary folder before exfiltration. One example function we observed is used to steal the victim’s Facebook Ads account that has hardcoded with Vietnamese words for Account rights, Threshold, Spent, Time Zone, and Date Created, etc.

The campaign  

Talos observed that CoralRaider is conducting a malicious campaign targeting victims in multiple countries in Asia and Southeast Asia, including India, China, South Korea, Bangladesh, Pakistan, Indonesia and Vietnam. 

The initial vector of the campaign is the Windows shortcut file. We are unclear on the technique the actor used to deliver the LNKs to the victims. Some of the shortcut file filenames that we observed during our analysis are:

• 자세한 비디오 및 이미지.lnk
• 設計內容+我的名片.lnk
• run-dwnl-restart.lnk
• index-write-upd.lnk
• finals.lnk
• manual.pdf.lnk
• LoanDocs.lnk
• DoctorReferral.lnk
• your-award.pdf.lnk
• Research.pdf.lnk
• start-of-proccess.lnk
• lan-onlineupd.lnk
• refcount.lnk

We also discovered a few notable unique drive serial numbers from the metadata of the Windows Shortcut files:

• A0B4-2B36
• FA4C-C31D
• 94AA-CEFB
• 46F7-AF3B

The attack begins when a user opens a malicious Windows shortcut file, which downloads and executes an HTML application file (HTA) from an attacker-controlled download server. The HTA file executes an embedded obfuscated Visual Basic script. The malicious Visual Basic script executes an embedded PowerShell script in the memory, which decrypts and sequentially executes three other PowerShell scripts that perform anti-VM and anti-analysis checks, bypass the User Access Controls, disables the Windows and application notifications on the victim’s machine, and finally downloads and run the RotBot. 

RotBot, the QuasarRAT client variant, in its initial execution phase, performs several detection evasion checks on the victim machine and conducts system reconnaissance. RotBot then connects to a host on a legitimate domain, likely controlled by the threat actor, and downloads the configuration file for the RotBot to connect to the C2. CoralRaider uses the Telegram bot as the C2 channel in this campaign. 

After connecting to the Telegram C2, RotBot loads the payload XClient stealer onto the victim memory from its resource and runs its plugin program. The XClient stealer plugin performs anti-VM and anti-virus software checks on the victim's machine. It executes its functions to collect the victim's browser data, including cookies, stored credentials, and financial information such as credit card details. It also collects the victim’s data from social media accounts, including Facebook, Instagram, TikTok business ads, and YouTube. It also collects the application data from the Telegram desktop and Discord application on the victim's machine. The stealer plugin can capture screenshots of the victim’s desktop and save them as a PNG file in the victim's machine’s temporary folder. With PNG files, the stealer plugin dumps the collected victim’s data from the browser and social media accounts in a text file and creates a ZIP archive. The PNG and ZIP files are exfiltrated to the attacker's Telegram bot C2.

RotBot loads and runs the payload  

RotBot, a remote access tool (RAT) compiled on Jan. 9, 2024, is downloaded and runs on the victim machine disguised as a Printer Subsystem application “spoolsv.exe.” RotBot is a variant of the QuasarRAT client that the threat actor has customized and compiled for this campaign. 

During its initial execution, RotBot performs several checks on the victim’s machine to evade detection, including IP address, ASN number, and running processes of the victim’s machine. It performs reconnaissance of system data on the victim machine. It also configures the internet proxy on the victim machine by modifying the registry key: 

Software\Microsoft\Windows\CurrentVersion\Internet 

Settings with the values:

ProxyServer = 127.0.0.1:80

ProxyEnable = 1

We observed that RotBot discovered in this campaign creates mutex in the victim machine as the infection markers​​ using the hardcoded strings in the binary.

RotBot loads and runs the XClient stealer module from its resources and uses the configuration parameters for its Telegram C2 bot from the downloaded configuration file. 

XClient stealer targets victims’ social media accounts. 

The XClient stealer sample we analyzed in this campaign is a .Net executable compiled on Jan. 7, 2024. It has extensive information-stealing capability through its plugin module and various modules for performing remote administrative tasks. 

XClient stealer has three primary functions that help it to avoid the radar. First, it will do virtual environment evasion if the victim’s machine runs in VMware or VirtualBox. It also checks if a DLL called sbieDll.dll exists in the victim machine file system to detect if it runs in the Sandboxie environment. XClient stealer also checks if anti-virus software, including AVG, Avast, and Kaspersky, is running on the victim’s machine. 

After bypassing all the checking functions, the XClient stealer captures the victim’s machine screenshot, saves it with the “.png” extension in the victim’s temporary user profile folder, and sends it to C2 through the URL “/sendPhoto.” 

XClient stealer steals victims’ social media web application credentials, browser data, and financial information such as credit card details. It targets Chrome, Microsoft Edge, Opera, Brave, CocCoc, and Firefox browser data files through the absolute paths of the respective browser installation paths. It extracts the contents of the browser database to a text file in the victim’s profile local temporary folder. 

XClient stealer hijacks and steals various Facebook data from the victim’s Facebook account. It sets custom HTTP header metadata along with the victim’s stolen Facebook cookie, and the username sends requests to Facebook APIs through the URLs below.

It checks if the victim’s Facebook is a business or ads account and uses regular expressions to search for access_token, assetID, and paymentAccountID. Using Facebook graph API, XClient attempts to collect an extensive list of information from the victim’s account, shown in the table below.

XClient stealer also collects the financial information from the victims’ Facebook business and ads accounts.

 Using the graph API, XClient stealer retrieves victims’ account friend list details and pictures. 

XClient stealer also targets the victim’s Instagram account and YouTube accounts through the URLs and collects various information, including username, badge_count, appID, accountSectionListRenderer, contents, title, data, actions, getMultiPageMenuAction, menu, multiPageMenuRenderer, sections and hasChannel. It collects the application data from the Telegram desktop and Discord application on the victim’s machine. XClient also collects the data from the victim’s TikTok business account and checks for business ads. 

Talos compiled the hardcoded HTTP request header metadata the XClient stealer uses in this campaign while retrieving the victim’s information from Facebook, Instagram, and YouTube accounts. 

Finally, the XClient stealer stores the victim’s social media data, which is collected into a text file in the local user profile temporary folder and creates a ZIP archive. The ZIP files were exfiltrated to the Telegram C2 through the URL “/sendDocument”.

Talos’ research of this campaign focused on discovering and disclosing a new threat actor of Vietnamese origin and their payloads. Additional technical details of the attack chain components of this campaign can be found in the report published by the researchers at QiAnXin Threat Intelligence Center. 

Coverage

Cisco Secure Endpoint (formerly AMP for Endpoints) is ideally suited to prevent the execution of the malware detailed in this post. Try Secure Endpoint for free here.

Cisco Secure Web Appliance web scanning prevents access to malicious websites and detects malware used in these attacks.

Cisco Secure Email (formerly Cisco Email Security) can block malicious emails sent by threat actors as part of their campaign. You can try Secure Email for free here.

Cisco Secure Firewall (formerly Next-Generation Firewall and Firepower NGFW) appliances such as Threat Defense Virtual, Adaptive Security Appliance and Meraki MX can detect malicious activity associated with this threat.

Cisco Secure Malware Analytics (Threat Grid) identifies malicious binaries and builds protection into all Cisco Secure products.

Umbrella, Cisco's secure internet gateway (SIG), blocks users from connecting to malicious domains, IPs and URLs, whether users are on or off the corporate network. Sign up for a free trial of Umbrella here.

Cisco Secure Web Appliance (formerly Web Security Appliance) automatically blocks potentially dangerous sites and tests suspicious sites before users access them.

Additional protections with context to your specific environment and threat data are available from the Firewall Management Center.

Cisco Duo provides multi-factor authentication for users to ensure only those authorized are accessing your network.

Open-source Snort Subscriber Rule Set customers can stay up to date by downloading the latest rule pack available for purchase on Snort.org. Snort SID for this threat is 63192.

ClamAV detections are also available for this threat:

Lnk.Downloader.CoralRaider-10024620-0

Html.Downloader.CoralRaider-10025101-0

Win.Trojan.RotBot-10024631-0

Win.Infostealer.XClient-10025106-2

Indicators of Compromise

Indicators of Compromise associated with this threat can be found here.

• Cisco Talos observed a surge in GhostSec, a hacking group’s malicious activities since this past year.
• GhostSec has evolved with a new GhostLocker 2.0 ransomware, a Golang variant of the GhostLocker ransomware.
• The GhostSec and Stormous ransomware groups are jointly conducting double extortion ransomware attacks on various business verticals in multiple countries. 
• GhostLocker and Stormous ransomware have started a new ransomware-as-a-service (RaaS) program STMX_GhostLocker, providing various options for their affiliates. 
• Talos also discovered two new tools in GhostSec arsenal, the “GhostSec Deep Scan tool” and “GhostPresser,” both likely being used in the attacks against websites.

Victimology of ransomware attacks

Talos observed the GhostSec and Stormous ransomware groups operating together to conduct several double extortion attacks using the GhostLocker and StormousX ransomware programs against the victims in Cuba, Argentina, Poland, China, Lebanon, Israel, Uzbekistan, India, South Africa, Brazil, Morocco, Qatar, Turkiye, Egypt, Vietnam, Thailand and Indonesia according to our assessment of the disclosure messages posted by the group in their Telegram channels and Stormous ransomware data leak site.  

The collaborative operation affected victims across various business verticals, according to disclosures made by the groups in their Telegram channels.

Talos’ observation in GhostSec’s Telegram channels highlighted the group’s continued attacks on Israel’s Industrial systems, critical infrastructure and technology companies. On Nov. 12, 2023, they claimed that the affected organizations also included the Ministry of Defense in Israel.

GhostSec has remained active since this past year

GhostSec is a hacker group that claims to be one of a modern-day Five Families group that includes ThreatSec, Stormous, Blackforums and SiegedSec on their Telegram channels. GhostSec is financially motivated, conducting single and double extortion attacks on victims across various geographies. They have also conducted several denial-of-service (DoS) attacks and have taken down victims’ websites, according to their Telegram channel messages. Their claims also showed us that their primary focus is raising funds for hacktivists and threat actors through their cybercriminal activities. 

The actor’s name, GhostSec, resembles the well-known hacktivist Ghost Security Group, primarily focusing on counterterrorism efforts and targeting pro-ISIS websites. The Ghost Security Group mentioned in their blog that another hacking group mimics their identity. 

In October 2023, GhostSec announced a new ransomware-as-a-service (RaaS) framework called GhostLocker. After their successful collaborative operations with the Stormous ransomware group in July 2023 against Cuban ministries, on Oct. 14, 2023, the Stormous gang announced that they would use the GhostLocker ransomware program in addition to their StormousX program. 

Since then, the GhostSec and Stormous ransomware groups have jointly conducted double extortion ransomware attacks targeting victims across various business verticals in multiple countries. Along with the ransomware attacks, GhostSec seemed to be conducting attacks against corporate websites, including a national railway operator in Indonesia and one of Canada’s leading energy companies. They have likely leveraged their GhostPresser tool along with the cross-site scripting attack technique to compromise the websites. 

On Feb. 24, 2024, Stormous group mentioned on “The Five Families” Telegram channel that they have started their new ransomware-as-a-service (RaaS) program “STMX_GhostLocker” along with their partners in GhostSec. The new program is made up of three categories of services for the affiliates: paid, free, and another for the individuals without a program who only want to sell or publish data on their blog (PYV service). 

The group has shared their working model flow diagrams for member and non-member affiliates on their Telegram channels.

Stormous ransomware and GhostSec have rebuilt the new official blog of their RAAS program Stmx_GhostLocker on the TOR network, with features for the affiliates to join their program and disclose their victim’s data. Their blog dashboard shows the count of victims and disclosures of victims’ information with a link to their leaked data. They also display the largest ransom as $500,000 USD — we are not sure if that is the highest ransom payment they have received. 

Evolution of GhostLocker 2.0 ransomware 

In November 2023, GhostSec announced a newer version of their GhostLocker ransomware called GhostLocker 2.0. Recently we observed that they have again started advertising their latest Golang version “GhostLocker 2.0” by calling it “GhostLocker V2” and mentioning their ongoing work on the GhostLocker V3, indicating their continuous evolution in developing their toolset. 

GhostLocker 2.0 encrypts the files on the victim’s machine using the file extension “.ghost” and drops and opens a ransom note. The ransom note has changed from its previous version, where the operator tells users to secure the encryption ID displayed in the ransom note and share it with them in their chat service during the negotiation by clicking “Click me.” The operator also mentions that the victim’s stolen data will be disclosed if they fail to contact them in seven days. 

The GhostLocker RAAS has a C2 panel where the affiliates can get an overview of their attacks and gains. When deployed on the victim’s machine, the ransomware binaries will register to the C2 panel, and the affiliates can track the encryption status on the victim’s machine. Talos discovered the GhostLocker 2.0 C2 server with the IP address 94[.]103[.]91[.]246 located in Moscow, Russia. We observed that the geolocation of the C2 server is similar to that of the C2 servers of earlier versions of the GhostLocker ransomware that security researchers at Uptycs reported. 

GhostLocker RAAS provides its affiliates with the ransomware builder, which contains configuration options, including the mode of persistence that the ransomware binary can establish after being successfully run on the victim machine, target directories to encrypt, and techniques to evade the detections, such as killing the defined processes or services or running the arbitrary command to kill the scheduled task or bypass the User Account Controls (UAC). 

Talos discovered the new variant of GhostLocker ransomware, “GhostLocker 2.0” in the wild on Nov. 15, 2023. The majority of the ransomware functionality of GhostLocker 2.0 remains the same as that of its earlier version GhostLocker, which was written in Python, excluding the watchdog component that the operator had used in earlier versions to start the dropped ransomware binary from the victim’s machine Windows Startup location and the AES encryption key length of 256 bits with that of 128 bits in the earlier version. 

During the initial execution, GhostLocker 2.0 copies itself to the Windows Startup folder to establish persistence. It also generates a random string of 32 bytes and uses the generated string as the filename for its dropped copy in the Windows Startup folder. 

After establishing the persistence, the ransomware establishes the connection to the C2 server through the URL hxxp[://]94[.]103[.]91[.]246[/]incrementLaunch.

After establishing a successful connection with the C2 server, the ransomware generates the secret key and the encryption ID and gathers the victim’s IP address, infection date and other information from its configuration parameters, including encryption status, ransom amount and a victim identifier string, to create a JSON file in the victim’s machine memory.

The generated JSON file is sent to the C2 server through the URL hxxp[://]94[.]103[.]91[.]246[/]addInfection to register the victim’s machine infection in the C2 panel.

After registering the victim’s machine infection with the C2 panel, the ransomware attempts to terminate the defined processes or services or Windows scheduled tasks from its configuration parameters in the victim’s machine to evade detection. 

GhostLocker 2.0 searches for the target files on the victim’s machine according to the file extension list defined by the threat actor, and before the encryption routine starts, it will upload the target files to the C2 server through the URL “hxxp[://]94[.]103[.]91[.]246[/]upload” using HTTP post method. In the GhostLocker 2.0 sample we analyzed, the actor has configured the ransomware to exfiltrate and encrypt the files that have file extensions .doc, .docx, .xls and .xlsx. 

After successfully exfiltrating, GhostLocker 2.0 encrypts the targeted files and appends “.ghost” as the file extension for the encrypted files. During the encryption process, GhostLocker 2.0 skips the “C:\Windows” folder. After completing the encryption routine, the ransomware drops the embedded ransom note to an HTML file with the filename “Ransomnote.html” on the victim’s desktop and launches it using the Windows `Start` command. 

Other tools likely used to scan and compromise websites 

Talos’ research uncovered two new tools in GhostSec’s arsenal that the hacking group claimed to have used in compromising legitimate websites. One of them is the “GhostSec Deep Scan toolset” to scan legitimate websites recursively, and another is a hack tool to perform cross-site scripting (XSS) attacks called “GhostPresser.”

GhostSec Deep Scan Tool

The GhostSec deep scan toolset is a Python utility that an attacker can use to scan the websites of their potential targets. 

The tool has several modules to perform the following scans on the targeted websites:

• Perform a user-specific search. 
• Scans multiple websites.
• Extract the hyperlinks on the website. 
• Performs a deep scan and analyzes the technologies used to build the web page.
• Scans the security protocols to detect the SSL/TLS and HSTS (HTTP Strict Transport Security).
• Perform the website content analysis and extract the contents to a file.
• Performs a WhoIs lookup.
• Checks for the existence of any broken links in the website.

The tool also contains placeholders to perform specific functions including SSL analysis, DNS lookup, checks for robots.txt and sitemap.xml, CVE scans on the targeted website, and an advanced search based on the file type, date range and the custom criteria of the websites, indicating the GhostSec’s continuous evolution of tools in their arsenal. 

One of the modules that stood out to us is the `deep_scan` function that the actor has defined to parse and scrape information from the targeted web pages and assess the technologies used in the web page. It is done by using the Python libraries Beautiful Soup, a Python package used for parsing data out of HTML and XML files, and the BuiltWith Python library, a Python package used to detect the technology used by a website, such as Apache, JQuery and WordPress. 

GhostPresser: A WordPress hack tool 

GhostPresser, an admin bypass and hacking tool targeting the WordPress content management system, is a shell script that GhostSec claims to have used in an XSS attack against a legitimate website in Canada. The tool appears to be under enhancement process as we spotted several placeholders in the tool to include functionalities to perform audits on the targeted websites. We are not sure at this moment about what type of audits the threat actor intends to implement in their tool. 

A threat actor can achieve the following actions after successfully injecting the GhostPresser into a targeted website on WordPress. 

• Bypass logins and perform actions such as test cookies. 
• Activate and deactivate a plugin. 
• Change WordPress settings.
• Create a new user. 
• Update WordPress core information. 
• Functions to install a new theme.

Below is an example of the function in the GhostPresser to install new themes in WordPress.

Coverage

Cisco Secure Endpoint (formerly AMP for Endpoints) is ideally suited to prevent the execution of the malware detailed in this post. Try Secure Endpoint for free here.

Cisco Secure Web Appliance web scanning prevents access to malicious websites and detects malware used in these attacks.

Cisco Secure Email (formerly Cisco Email Security) can block malicious emails sent by threat actors as part of their campaign. You can try Secure Email for free here.

Cisco Secure Firewall (formerly Next-Generation Firewall and Firepower NGFW) appliances such as Threat Defense Virtual, Adaptive Security Appliance and Meraki MX can detect malicious activity associated with this threat.

Cisco Secure Malware Analytics (Threat Grid) identifies malicious binaries and builds protection into all Cisco Secure products.

Umbrella, Cisco's secure internet gateway (SIG), blocks users from connecting to malicious domains, IPs and URLs, whether users are on or off the corporate network. Sign up for a free trial of Umbrella here.

Cisco Secure Web Appliance (formerly Web Security Appliance) automatically blocks potentially dangerous sites and tests suspicious sites before users access them.

Additional protections with context to your specific environment and threat data are available from the Firewall Management Center.

Cisco Duo provides multi-factor authentication for users to ensure only those authorized are accessing your network.

Open-source Snort Subscriber Rule Set customers can stay up to date by downloading the latest rule pack available for purchase on Snort.org. Snort SIDs for this threat are 62983-62989, and 300818-300820. 

ClamAV detections are also available for this threat:

Win.Ransomware.GhostSec-10020906-0

Indicators of Compromise

Indicators of Compromise associated with this threat can be found here.