OffensiveNim

My experiments in weaponizing Nim for implant development and general offensive operations.

Table of Contents

• OffensiveNim
  • Table of Contents
  • Why Nim?
  • Examples in this repo that work
  • Examples that are a WIP
  • Compiling the examples in this repo
    • Easy Way (Recommended)
    • Hard way (For the bold)
  • Cross Compiling
  • Interfacing with C/C++
  • Creating Windows DLLs with an exported DllMain
    • Creating XLLs
  • Optimizing executables for size
  • Reflectively Loading Nim Executables
  • Executable size difference when using the Winim library vs without
  • Opsec Considerations
  • Writing Nim without the Nim Runtime
  • Converting C code to Nim
  • Language Bridges
  • Debugging
  • Setting up a dev environment
  • Pitfalls I found myself falling into
  • Interesting Nim libraries
  • Nim for implant dev links
  • Contributors

Why Nim?

• Compiles directly to C, C++, Objective-C and Javascript.
• Since it doesn't rely on a VM/runtime does not produce what I like to call "T H I C C malwarez" as supposed to other languages (e.g. Golang)
• Python inspired syntax, allows rapid native payload creation & prototyping.
• Has extremely mature FFI (Foreign Function Interface) capabilities.
• Avoids making you actually write in C/C++ and subsequently avoids introducing a lot of security issues into your software.
• Super easy cross compilation to Windows from *nix/MacOS, only requires you to install the mingw toolchain and passing a single flag to the nim compiler.
• The Nim compiler and the generated executables support all major platforms like Windows, Linux, BSD and macOS. Can even compile to Nintendo switch , IOS & Android. See the cross-compilation section in the Nim compiler usage guide
• You could technically write your implant and c2 backend both in Nim as you can compile your code directly to Javascript. Even has some initial support for WebAssembly's

Examples in this repo that work