Introduction
This is assignment #7 of the SLAE x86 Exam objectives.
Objectives
- Create a custom crypter like the one shown in the “crypters” video
- Free to use any existing encryption schema
- Can use any programming language
Category: C programming
ASM Polymorphic shellcode (SLAE x86 Assignment #6)
Introduction
This is assignment #6 of the SLAE x86 Exam objectives.
Objectives
- Take up 3 shellcodes from Shell-Storm and create polymorphic versions of them to beat pattern matching
- The polymorphic versions cannot be larger than 150% of the existing shellcode
- Bonus points for making it shorter in length than original
C: changing shellcode bytes at the middle (or at shellcode offset)
The Problem
While writing a bindshell shellcode for the SLAE32 course Assignment #1, which will be described in details another blog post, there was an interesting issue while coding the C program. As the exercise required some flexibility on passing the port as an argument, the issue was that there is not a direct way to alter the 2 bytes of shellcode in C, so if you are looking for a way to change some bytes at the middle or at an offset of your shellcode the solution follows below.
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