Travel back to a simpler time with me and let's pwn some old CTF challenges! This week we'll be looking at shellcoding, ROP, and heap challenges that we'll e...

This challenge presents a classic shellcoding problem with a twist: instead of writing shellcode to spawn a shell or read a file, we must write ultra-compact x86-64 shellcode that performs Base64 decoding. The challenge runs our shellcode inside the Unicorn CPU emulator and verifies that our decoder correctly transforms a randomly generated Base64-encoded secret back to its original bytes. The core constraint is brutally simple but difficult to achieve:

Exploits represent any piece of code, data or sequence of commands that targets a vulnerable application for the purpose of gaining unauthorized access. Log4j is one of the most popular recent exploit...

Introduction Modern malware and red team operations often evade detection by avoiding the Import Address Table (IAT), a common target for static analysis. Instead, techniques like Process Environment Block (PEB) traversal enable dynamic resolution of critical APIs like `LoadLibraryA` and MessageBoxA. This article explores how shellcode leverages PEB traversal to bypass IAT dependencies, enhancing stealth and flexibility. Learning Objectives…

The CoffeeLoader malware employs a GPU shellcoding technique to avoid detection and deploy information-stealing programs. This technique allows the malware to run stealthily by exploiting the GPU's computing capabilities, making detection more difficult for traditional security solutions. The primary impact is the theft of sensitive information from infected systems.

When it comes to thinking about shellcode, normally we don’t think of the MSVC toolchain. Maybe we’ll think of MASM, the assembler of MSVC, but we certainly won’t think of the C compiler. We typically...

Well it’s been a fun ride, but we’ve reached our destination. 🚗 Time to wrap things up with our Assembly and Shellcoding 101 course and move on to the next exciting topic on this blog. Don’t know wha...

Today is reverse shell day! I’m sure most of you were hoping we’d eventually be able to discuss writing a reverse shell using x64 assembly, and today just so happens to be that day. 😸 We’re going to...

We begin the adventure with assembly and shellcoding on Windows x64. In this post, we run the WinAPI function without any imports.