🧠 C2-Windows-x64 - Command & Control Framework

A Command & Control (C2) framework written in C++ for Windows x64 systems.

This project simulates a real-world offensive security infrastructure used to remotely control multiple machines (agents) from a central server.

It is designed to demonstrate how attackers (or red teamers) build scalable systems to:

• maintain access to machines
• execute commands remotely
• manage multiple targets simultaneously

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🚀 Features

• 🧠 Full C2 architecture (server ↔ agents)
• 🔗 TCP communication using Winsock (low-level networking)
• 👥 Multi-agent handling with select() (no threads per client)
• 🔐 Time-based authentication (anti-unauthorized access)
• 💻 Remote command execution via hidden processes
• 🪟 Stealth agent (no console / background execution)
• 📄 Logging system (server-side activity tracking)
• 🎨 ANSI CLI interface (operator feedback)

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🎯 What this project demonstrates

This is NOT a simple reverse shell.

It implements core concepts found in real C2 frameworks:

• Agent ↔ Server communication protocol
• Authentication layer
• Multi-client orchestration
• Command execution pipeline
• Basic OPSEC considerations (stealth, timing, minimal footprint)

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📁 Project Structure

src/
├── client/                # Agent (executed on target machine)
│   └── main.cpp
├── server/                # C2 server (operator side)
│   ├── main.cpp
│   ├── class/
│   │   ├── client.cpp
│   │   └── server.cpp
│   ├── cli/
│   │   └── cli.cpp       # Operator command interface
│   └── log/
│       └── log.cpp

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⚙️ Build

Using MinGW / MSYS2:

mingw32-make re

🔧 Generated binaries

• client.exe → Agent (debug mode)
• client_no_console.exe → Agent (stealth mode)
• server.exe → C2 server

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▶️ Usage

1. Start the C2 server

./server.exe

2. Execute the agent on a target machine

./client.exe

or stealth mode:

./client_no_console.exe

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🧠 Architecture

🔌 Agent lifecycle

1. Connects to the C2 server
2. Sends authentication token
3. Sends hostname (target identification)
4. Waits for commands
5. Executes instructions and returns output

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🔑 Authentication system

• Shared secret hardcoded
• Time-based rotation (every 30 seconds)
• Prevents unauthorized connections

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💻 Remote command execution

• Commands sent from C2 server
• Executed using CreateProcess
• No visible window (CREATE_NO_WINDOW)
• Output captured via pipes
• Sent back to operator

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👥 Multi-agent management

• Uses select() for scalability

• No thread-per-client overhead

• Tracks:

  • authentication state
  • hostname
  • connection time

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📄 Logging

Logs stored in:

other/logs/log.txt

Example:

Succes auth

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🧪 Example Operations

• Execute system commands remotely
• Identify active machines (hostname)
• Drop unauthenticated agents
• Blacklist specific IPs

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⚠️ Disclaimer

This project is for educational and authorized security research only.

It is intended to demonstrate:

• how C2 infrastructures work
• how attackers manage remote systems
• how defensive teams can understand these mechanisms

Do NOT use on systems without explicit permission.

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💡 Roadmap

• 🔒 TLS encryption (secure communications)
• 🧩 Modular command system (plugin-based tasks)
• 📊 Advanced logging (timestamps, agent IDs)
• 🔁 Auto-reconnect agents (persistence)
• 🌐 Cross-platform agents (Linux)
• 🧠 Task queue system (async execution)
• 📡 Advanced OPSEC features

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🧑‍💻 Author

Built as part of a low-level systems and offensive security learning journey.

Focus: scalability, realism, and understanding of modern C2 design.