Following a recent engagement, I had the opportunity to check and verify some possible vulnerabilities on an ASP .NET application. Despite not being the deepest technical nor innovative blog post you could find on the net, I have decided to post it anyway in order to explain the methodology I adopt to verify possible vulnerabilities. […]

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Banner Image by Sergio Kalisiak TL; DR: I will explain, in details, how to trigger PrintDemon exploit and dissect how I’ve discovered a new 0-day; Microsoft Windows EoP CVE-2020-1337, a bypass of PrintDemon’s recent patch via a Junction Directory (TOCTOU). Contents PrintDemon primer, how the exploit works? PrinterPort WritePrinter Shadow Job File Binary Diffing CVE-2020-1048 […]

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TL;DR: Shenzhen Sricctv Technology Sricam CMS (SricamPC.exe) <= v.1.0.0.53(4) and DeviceViewer (DeviceViewer.exe) <= v.3.10.12.0 (CVE-2019-11563) are affected by a local Stack Buffer Overflow. By creating a specially crafted “Username” and copying its value in the “User/mail” login field, an attacker will be able to gain arbitrary code execution in the context of the currently logged-in […]

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During this period of social isolation, a friend of mine proposed to play some online “board games”. He proposed “Tabletopia”: a cool sandbox virtual table with more than 800 board games. Tabletopia is both accessible from its own website and from the Steam’s platform. While my friends decided to play from their browser, I’ve opted […]

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Assignment #7: Custom Shellcode Crypter Seventh and last SLAE’s assignment requires to create a custom shellcode crypter. Since I had to implement an entire encryption schema both in python as an helper and in assembly as the main decryption routine, I’ve opted for something simple. I’ve chosen the Tiny Encryption Algorithm (TEA) as it does […]

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Assignment #6: Polymorphic Shellcode Sixth SLAE’s assignment requires to create three different (polymorphic) shellcodes version starting from published Shell Storm’s examples. I’ve decided to take this three in exam: http://shell-storm.org/shellcode/files/shellcode-752.php – linux/x86 execve (“/bin/sh”) – 21 bytes http://shell-storm.org/shellcode/files/shellcode-624.php – linux/x86 setuid(0) + chmod(“/etc/shadow”,0666) – 37 bytes http://shell-storm.org/shellcode/files/shellcode-231.php – linux/x86 open cd-rom loop (follows “/dev/cdrom” symlink) […]

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Assignment #5: Metasploit Shellcode Analysis Fifth SLAE’s assignment requires to dissect and analyse three different Linux x86 Metasploit Payload. Metasploit currently has 35 different payloads but almost half of it are Meterpreter version, thus meaning staged payloads. I’ve then decided to skip meterpreter payloads as they involve multiple stages and higher complexity that will break […]

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Assignment #4: Custom Shellcode Encoder As the 4th SLAE’s assignment I was required to build a custom shellcode encoder for the execve payload, which I did, here how. Encoder Implementations I’ve decided to not relay on XORing functionalities as most antivirus solutions are now well aware of this encoding schema, the same reason for which […]

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This post will be a bit different from the usual technical stuff, mostly because I was not able to find any reliable solution on Internet and I would like to help other people having the same doubt/question, it’s nothing advanced, it’s just something useful that I didn’t see posted before. During a recent engagement I […]

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Assignment #3: Egghunter This time the assignment was very interesting, here the requirements: study an egg hunting shellcode and create a working demo, it should be configurable for different payloads. As many before me, I’ve started my research journey with Skape’s papers: “Searching Process Virtual Address Space”. I was honestly amazed by the paper content, […]

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