[ExpDev] Custom Shellcode Encoder

bigb0ss
4 min readApr 22, 2021

What is Encoder?

In computer systems, an encoder can be used for various purposes. For example, Base64 encodes binary data into an ASCII characters which are known to pretty much every computer system. Or one may use an encoder to mangle their own code to potentially bypass a security product such as AV. Today, I will demonstrate a simple custom encoding scheme for a x86 shellcode.

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bigb0ss

OSWE | OSCE | OSCP | CREST | Lead Offensive Security Engineer — All about Penetration Test, Red Team, Cloud Security, Web Application Security