RsaCtfTool

RSA multi attacks tool : uncipher data from weak public key and try to recover private key Automatic selection of best attack for the given public key

Attacks :

Weak public key factorization
Wiener's attack
Hastad's attack (Small public exponent attack)
Small q (q < 100,000)
Common factor between ciphertext and modulus attack
Fermat's factorisation for close p and q
Gimmicky Primes method
Past CTF Primes method
Self-Initializing Quadratic Sieve (SIQS) using Yafu (https://github.com/DarkenCode/yafu.git)
Common factor attacks across multiple keys
Small fractions method when p/q is close to a small fraction
Boneh Durfee Method when the private exponent d is too small compared to the modulus (i.e d < n^0.292)
Elliptic Curve Method
Pollards p-1 for relatively smooth numbers
Mersenne primes factorization
Factordb
Londahl
Noveltyprimes
Partial q
Primefac
Qicheng
Same n, huge e

Usage

usage: RsaCtfTool.py [-h] [--publickey PUBLICKEY] [--timeout TIMEOUT]
                     [--createpub] [--dumpkey] [--ext]
                     [--uncipherfile UNCIPHERFILE] [--uncipher UNCIPHER]
                     [--verbosity {CRITICAL,ERROR,WARNING,DEBUG,INFO}]
                     [--private] [--ecmdigits ECMDIGITS] [-n N] [-p P] [-q Q]
                     [-e E] [--key KEY]
                     [--attack {mersenne_primes,pollard_p_1,smallfraction,smallq,boneh_durfee,noveltyprimes,ecm,factordb,wiener,siqs,pastctfprimes,partial_q,comfact_cn,hastads,fermat,nullattack,primefac,commonfactors,same_n_huge_e,all}]

Mode 1 : Attack RSA (specify --publickey or n and e)

publickey : public rsa key to crack. You can import multiple public keys with wildcards.
uncipher : cipher message to decrypt
private : display private rsa key if recovered

Mode 2 : Create a Public Key File Given n and e (specify --createpub)

n : modulus
e : public exponent

Mode 3 : Dump the public and/or private numbers (optionally including CRT parameters in extended mode) from a PEM/DER format public or private key (specify --dumpkey)

key : the public or private key in PEM or DER format

Uncipher file

./RsaCtfTool.py --publickey ./key.pub --uncipherfile ./ciphered\_file

Print private key

./RsaCtfTool.py --publickey ./key.pub --private

Attempt to break multiple public keys with common factor attacks or individually- use quotes around wildcards to stop bash expansion

./RsaCtfTool.py --publickey "*.pub" --private

Generate a public key

./RsaCtfTool.py --createpub -n 7828374823761928712873129873981723...12837182 -e 65537

Dump the parameters from a key

./RsaCtfTool.py --dumpkey --key ./key.pub

Factor with ECM when you know the approximate length in digits of a prime

./RsaCtfTool.py --publickey key.pub --ecmdigits 25 --verbose --private

For more examples, look at test.sh file

Requirements

GMPY2
SymPy
PyCrypto
Requests
Libnum
SageMath : optional but advisable

Ubuntu 18.04 and Kali specific Instructions

git clone https://github.com/Ganapati/RsaCtfTool.git
sudo apt-get install libgmp3-dev libmpc-dev
pip3 install -r "requirements.txt"
python3 RsaCtfTool.py

MacOS-specific Instructions

If pip3 install -r "requirements.txt" fails to install requirements accessible within environment, the following command may work.

easy_install `cat requirements.txt`

Todo

Brainstorm moar attack types !

epicn1337 / RsaCtfTool