JWT cracker - JWT Brute Force Cracker Written in C

A multi-threaded JWT brute-force cracker written in C. If you are very lucky or have a huge computing power, this program should find the secret key of a JWT token, allowing you to forge valid tokens. This is for testing purposes only, do not put yourself in trouble.

The tool is based in the Apple Base64 implementation.

Make sure you have openssl's headers installed. On Ubuntu you can install them with apt-get install libssl-dev
If you use a Mac, you can install OpenSSL with brew install openssl, but the headers will be stored in a different location:
make OPENSSL=/usr/local/opt/openssl/include OPENSSL_LIB=-L/usr/local/opt/openssl/lib

$ > ./jwtcrack eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiIxMjM0NTY3ODkwIiwibmFtZSI6IkpvaG4gRG9lIiwiYWRtaW4iOnRydWV9.cAOIAifu3fykvhkHpbuhbvtH807-Z2rI1FS3vX1XMjE
In the above example, the key is Sn1f. It takes approximately 2 seconds to crack on my Macbook.

  • No progress status
  • If you stop the program, you cannot start back where you were

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