jwt-hack

cargo install jwt-hack

brew install jwt-hack

sudo snap install jwt-hack

git clone https://github.com/hahwul/jwt-hack
cd jwt-hack
cargo install --path .

docker pull ghcr.io/hahwul/jwt-hack:latest

docker pull hahwul/jwt-hack:v2.6.0

jwt-hack decode eyJhbGciOiJIUzI1NiJ9.eyJzdWIiOiIxMjM0In0.CHANGED
jwt-hack decode COMPRESSED_JWT_TOKEN

# Decode JWE token structure
jwt-hack decode eyJhbGciOiJkaXIiLCJlbmMiOiJBMjU2R0NNIn0..ZHVtbXlfaXZfMTIzNDU2.eyJ0ZXN0IjoiandlIn0.ZHVtbXlfdGFn

# Shows JWE header, encrypted key, IV, ciphertext, and authentication tag

jwt-hack encode '{"sub":"1234"}' --secret=your-secret

jwt-hack encode '{"sub":"1234"}' --secret=your-secret --compress

# With Private Key
ssh-keygen -t rsa -b 4096 -E SHA256 -m PEM -P "" -f RS256.key
jwt-hack encode '{"a":"z"}' --private-key RS256.key --algorithm=RS256

# Basic JWE encoding
jwt-hack encode '{"sub":"1234", "data":"encrypted"}' --jwe --secret=your-secret

# JWE tokens are encrypted and can only be decrypted with the proper key
jwt-hack encode '{"sensitive":"data"}' --jwe

# With Secret (HMAC algorithms like HS256, HS384, HS512)
jwt-hack verify YOUR_JWT_TOKEN_HERE --secret=your-256-bit-secret

# With Private Key (for asymmetric algorithms like RS256, ES256, EdDSA)
jwt-hack verify YOUR_JWT_TOKEN_HERE --private-key path/to/your/RS256_private.key

# Dictionary attack
jwt-hack crack -w wordlist.txt JWT_TOKEN
jwt-hack crack -w wordlist.txt COMPRESSED_JWT_TOKEN

# Bruteforce attack
jwt-hack crack -m brute JWT_TOKEN --max=4
jwt-hack crack -m brute COMPRESSED_JWT_TOKEN --max=4

jwt-hack payload JWT_TOKEN --jwk-attack evil.com --jwk-trust trusted.com

# Full scan including weak secret detection and payload generation
jwt-hack scan JWT_TOKEN

# Skip secret cracking for faster results
jwt-hack scan JWT_TOKEN --skip-crack

# Skip payload generation
jwt-hack scan JWT_TOKEN --skip-payloads

# Use custom wordlist for weak secret detection
jwt-hack scan JWT_TOKEN -w custom_wordlist.txt

# Limit secret testing attempts
jwt-hack scan JWT_TOKEN --max-crack-attempts 50

# Start on localhost:3000 with API key protection
jwt-hack server --api-key your-api-key

# Example request (must include X-API-KEY when --api-key is set)
curl -s http://127.0.0.1:3000/health -H 'X-API-KEY: your-api-key'

# Start MCP server (communicates via stdio)
jwt-hack mcp

{
  "name": "decode",
  "arguments": {
    "token": "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9..."
  }
}

{
  "name": "encode",
  "arguments": {
    "json": "{\"sub\":\"1234\",\"name\":\"test\"}",
    "secret": "mysecret",
    "algorithm": "HS256"
  }
}

{
  "servers": {
    "jwt-hack": {
      "type": "stdio",
      "command": "jwt-hack",
      "args": [
        "mcp"
      ]
    }
  },
  "inputs": []
}

{
  "mcpServers": {
    "jwt-hack": {
      "command": "jwt-hack",
      "args": ["mcp"],
      "env": {}
    }
  }
}