Assignment #5: Metasploit Shellcode Analysis

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 libemu graph generation (which I find very useful to better explain shellcode’s operations). In this blog we are going to analyse the following shellcodes: linux/x86/shell_find_tag linux/x86/shell_find_port linux/x86/shell/bind_nonx_tcp As...


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SLAE – Assignment #4: Custom shellcode encoder

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. Stay updated, join VoidSec's Telegram Channel: https://t.me/voidsec_updates 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 I’ve skipped ROT13 and other “rotating” encoding. I thought of using some multiple weird shifting schema but that would have had...


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Perform a Nessus scan via port forwarding rules only

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 found myself in a strange network position. I had to perform a Nessus credentialed and patch checks on some Windows server, I was in a...


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SLAE – Assignment #3: Egghunter

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, it’s not only very well written and explained but it ‘s mind-blowing. Understanding why and how egg hunter shellcode should be crafted in such tailored way...


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SLAE – Assignment #2: Reverse TCP Shell

Assignment #2: Reverse TCP Shell Create a shell_reverse_tcp shellcode that connects back to an IP address, on a specific a port and execute a shell. The IP address and port number should be easy configurable. Again, instead of going for the path of writing a C TCP reverse shell from scratch, I decided to generate a raw Metasploit payload and analyze it with libemu. Analyzing the Shellcode All the code is also available on GitHub. This time the analysis will be a lot shorter...


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