Windows User Space Emulator

A high-performance Windows process emulator that operates at the syscall level, providing full control over process execution through comprehensive hooking capabilities.

Built in C++ and powered by the Unicorn Engine.

Note

The project is still in a very early, prototypy state. The code still needs a lot of cleanup and many features and syscalls need to be implemented. However, constant progress is being made :)

Key Features

• Syscall-Level Emulation: Instead of reimplementing Windows APIs, the emulator operates at the syscall level, allowing it to leverage existing system DLLs
• Advanced Memory Management: Supports Windows-specific memory types including reserved, committed, built on top of Unicorn's memory management
• Complete PE Loading: Handles executable and DLL loading with proper memory mapping, relocations, and TLS
• Exception Handling: Implements Windows structured exception handling (SEH) with proper exception dispatcher and unwinding support
• Threading Support: Provides a scheduled (round-robin) threading model
• State Management: Supports both full state serialization and fast in-memory snapshots
• Debugging Interface: Implements GDB serial protocol for integration with common debugging tools (IDA Pro, GDB, LLDB, VS Code, ...)

Perfect for security research, malware analysis, and DRM research where fine-grained control over process execution is required.

Building

Make sure to clone the repo including all submodules.

git clone https://github.com/momo5502/emulator.git
cd emulator
git submodule update --init --recursive

At the moment, the project is only compatible with 64 bit Windows, but that is being worked on: Issue 17

It requires CMake and uses CMake presets. Make sure to open an x64 Dev Cmd before running any of the commands.

Visual Studio 2022

To generate a Visual Studio solution, execute the following command:

cmake --preset=vs2022

The solution will be at build/vs2022/emulator.sln.

Ninja

To build the debug version using Ninja run:

cmake --workflow --preset=debug

You can also build the release variant:

cmake --workflow --preset=release

Running Tests

CTest is used for testing.

In Visual Studio, build the RUN_TESTS target.

With Ninja, execute the CTest command in the ninja build folder (e.g. build/release/):

ctest

Preview

YouTube Overview

Click here for the slides.