Shellab

Linux and Windows shellcode development/enrichment utility

Table of Contents

• Introduction
• Requirements
• Features
• TODO
• Usage
• Screenshots
• Contribution
• License

Introduction

Shellab is a tool that can be used to improve existing shellcodes and adapt them for personal needs. Developed to provide an alternative to msfvenom with new functionalities. Suitable for both Windows and Linux shellcode (32 and 64 bit).

Requirements

Shellab requires Radare2 and dependencies provided in requirements.txt file, you should install it running this command: $ sudo apt-get install radare2 && python3 -m pip install -r requirements.txt

Features

• Encode shellcode with custom encoder
• Generate stagers and egghunters (including sandwich and omelette egghunter)
• Inject shellcode into PE files
• Run shellcode on Linux
• Remove bad characters and null-bytes
• Perform experimental size reduction (by instructions replacement)
• Export shellcode in different executable formats (C, C#, Python, Powershell, hex, raw etc.)
• Add custom instructions, NOP slides and specific system calls

TODO

• Create more encoders
• Implement generation of fully alphanumeric shellcode
• Add shellcode comparison mechanism

Usage

This example will encode the input shellcode with "rot_xor" encoder, insert "xor eax, eax" instruction and 100 non-canonical NOP instructions in front of it, generate a bind stager (that will listen for the incoming shellcode on port 4444) and prepend the shellcode with exit() syscall.

Show help message:

List available components:

Generate the shellcode:

Contribution

If you have an idea for a new encoder, egghunter or stager, or just want to improve this tool, simply create a pull request :)

License

This software is under MIT License