tldr/pages/common/rsactftool.py.md

RsaCtfTool.py

RSA attack tool for CTF challenges - recover private keys from weak public keys and/or decrypt data. More information: https://github.com/RsaCtfTool/RsaCtfTool.

• Recover a private key from a public key file:

RsaCtfTool.py --publickey {{path/to/key.pub}} --private

• Decrypt a file using a public key:

RsaCtfTool.py --publickey {{path/to/key.pub}} --decryptfile {{path/to/ciphered_file}}

• Decrypt a specific ciphertext string:

RsaCtfTool.py --publickey {{path/to/key.pub}} --decrypt "{{ciphertext}}"

• Dump RSA key components (e.g., modulus, exponent) from a key file:

RsaCtfTool.py --dumpkey --key {{path/to/key.pub}}

• Run a specific attack (e.g., Fermat factorization) to recover the private key:

RsaCtfTool.py --publickey {{path/to/key.pub}} --private --attack fermat

• Generate a public key from modulus (n) and exponent (e):

RsaCtfTool.py --createpub -n {{modulus}} -e {{exponent}}

• Attempt all available attacks to recover the private key:

RsaCtfTool.py --publickey {{path/to/key.pub}} --private --attack all