sec-chisel-mcp

An MCP (Model Context Protocol) server for managing Chisel TCP/UDP tunnels. Enables AI assistants to create and manage secure tunneling connections through a remote host.

Features

• Server Management - Start chisel servers with SOCKS5 and reverse tunnel support
• Client Connections - Connect to chisel servers and establish tunnels
• Reverse Tunneling - Create reverse port forwards for accessing internal services
• SOCKS5 Proxy - Set up SOCKS5 proxies for traffic routing
• Port Forwarding - Create local-to-remote port forwards
• Process Management - Track, monitor, and stop active tunnels

Installation

# Clone the repository
git clone https://github.com/schwarztim/sec-chisel-mcp.git
cd sec-chisel-mcp

# Install dependencies
npm install

# Build
npm run build

Configuration

Claude Desktop

Add to your Claude Desktop configuration (~/.claude.json or similar):

{
  "mcpServers": {
    "chisel": {
      "command": "node",
      "args": ["/path/to/sec-chisel-mcp/dist/index.js"],
      "env": {
        "CHISEL_KALI_HOST": "kali",
        "CHISEL_DEFAULT_PORT": "8080"
      }
    }
  }
}

Environment Variables

Variable	Default	Description
CHISEL_KALI_HOST	kali	SSH hostname for the remote machine
CHISEL_DEFAULT_PORT	8080	Default chisel server port

Prerequisites

1. Chisel installed on the remote host

   # Install via script
   curl https://i.jpillora.com/chisel! | bash
   
   # Or via package manager (Kali/Debian)
   sudo apt install chisel

2. SSH access configured

   • Key-based authentication recommended
   • Host configured in ~/.ssh/config

Tools

Tool	Description
chisel_server	Start a chisel server with SOCKS5 and reverse tunnel support
chisel_client	Connect to a chisel server and create tunnels
chisel_reverse	Start a server configured for reverse tunneling
chisel_socks	Start a SOCKS5 proxy server
chisel_forward	Create a local port forward tunnel
chisel_status	Check status of active tunnels
chisel_stop	Stop one or all tunnels
chisel_list_processes	List all chisel processes on the remote host
chisel_version	Check chisel installation and version

Usage Examples

Start a Chisel Server

{
  "tool": "chisel_server",
  "arguments": {
    "port": "8080",
    "reverse": true,
    "socks5": true,
    "auth": "user:password"
  }
}

Create a Reverse Tunnel

Expose an internal service externally:

{
  "tool": "chisel_client",
  "arguments": {
    "server": "http://server:8080",
    "remotes": ["R:2222:localhost:22"]
  }
}

Set Up SOCKS5 Proxy

{
  "tool": "chisel_socks",
  "arguments": {
    "port": "8080"
  }
}

Connect a client:

chisel client <server>:8080 socks

Use with proxychains:

# Add to /etc/proxychains.conf
socks5 127.0.0.1 1080

Local Port Forward

Forward local traffic to a remote destination:

{
  "tool": "chisel_forward",
  "arguments": {
    "server": "http://pivot:8080",
    "localPort": "3389",
    "remoteHost": "10.10.10.100",
    "remotePort": "3389"
  }
}

Check Tunnel Status

{
  "tool": "chisel_status",
  "arguments": {}
}

Stop All Tunnels

{
  "tool": "chisel_stop",
  "arguments": {
    "force": false
  }
}

Chisel Remote Syntax

Chisel uses the following format for remote specifications:

<local-host>:<local-port>:<remote-host>:<remote-port>/<protocol>

Examples:

• 3000 - Forward local 3000 to server's 3000
• 3000:google.com:80 - Tunnel to external host
• R:2222:localhost:22 - Reverse port forward
• socks - SOCKS5 proxy connection
• R:socks - Reverse SOCKS proxy

Security Considerations

• Authentication: Use --auth user:password for production deployments
• Fingerprint Verification: Use --fingerprint on clients to verify server identity
• TLS Encryption: Consider using --tls-key and --tls-cert for encrypted transport
• Traffic Profile: Chisel traffic appears as HTTP/WebSocket traffic, useful for firewall evasion

Development

# Run in development mode
npm run dev

# Build for production
npm run build

# Start the server
npm start

References

• Chisel GitHub Repository
• Model Context Protocol
• HackTricks Tunneling Guide

License

MIT License - see LICENSE for details.