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
binary polynomial factoring
Euler method
Pollard Rho
Wolfram alpha
cm-factor
z3 theorem prover
Primorial pm1 gcd
Mersenne pm1 gcd
Fermat Numbers gcd
Fibonacci gcd
System primes gcd
Small crt exponent
Shanks's square forms factorization (SQUFOF)
Return of Coppersmith's attack (ROCA) with NECA variant
Dixon
brent (Pollard rho variant)
Pisano Period
NSIF Vulnerability, Power Modular Factorization, Near Power Factors

Usage

usage: RsaCtfTool.py [-h] [--publickey PUBLICKEY] [--timeout TIMEOUT]
                     [--createpub] [--dumpkey] [--ext] [--sendtofdb]
                     [--uncipherfile UNCIPHERFILE] [--uncipher UNCIPHER]
                     [--verbosity {CRITICAL,ERROR,WARNING,DEBUG,INFO}]
                     [--private] [--ecmdigits ECMDIGITS] [-n N] [-p P] [-q Q]

                     [-e E] [--key KEY] [--isconspicuous] [--convert_idrsa_pub] [--isroca] [--check_publickey]
                     [--attack {brent,fermat_numbers_gcd,comfact_cn,wiener,factordb,smallq,pollard_rho,euler,z3_solver,neca,cm_factor,mersenne_pm1_gcd,SQUFOF,small_crt_exp,fibonacci_gcd,smallfraction,boneh_durfee,roca,fermat,londahl,mersenne_primes,partial_q,siqs,noveltyprimes,binary_polinomial_factoring,primorial_pm1_gcd,pollard_p_1,ecm2,cube_root,system_primes_gcd,dixon,ecm,pastctfprimes,qicheng,wolframalpha,hastads,same_n_huge_e,commonfactors,pisano_period,nsif,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

Optionaly send the results back to factordb

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

Generate a public key

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

Dump the parameters from a key

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

Check a given private key for conspicuousness

./RsaCtfTool.py --key examples/conspicuous.priv --isconspicuous

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

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

NSIF Attack - factorization with GCD inverse modular exponent

time ./RsaCtfTool.py -n 1078615880917389544637583114473414840170786187365383943640580486946396054833005778796250863934445216126720683279228360145952738612886499734957084583836860500440925043100784911137186209476676352971557693774728859797725277166790113706541220865545309534507638851540886910549436636443182335048699197515327493691587 --attack nsif -e 10000

For more examples, look at test.sh file

Convert idrsa.pub to pem format

./RsaCtfTool.py --convert_idrsa_pub --publickey $HOME/.ssh/id_rsa.pub

Check if a given key or keys are roca

./RsaCtfTool.py --isroca --publickey "examples/*.pub"

Docker run

docker pull ganapati/rsactftool docker run -it --rm -v $PWD:/data ganapati/rsactftool <arguments>

Requirements

GMPY2
SymPy
PyCrypto
Requests
Libnum
SageMath : optional but advisable
Sage binaries

Ubuntu 18.04 and Kali specific Instructions

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

Fedora (33 and above) specific Instructions

git clone https://github.com/Ganapati/RsaCtfTool.git
sudo dnf install gcc python3-devel python3-pip python3-wheel gmp-devel mpfr-devel libmpc-devel
cd RsaCtfTool
pip3 install -r "requirements.txt"
python3 RsaCtfTool.py

If you also want the optional SageMath you need to do

sudo dnf install sagemath
pip3 install -r "optional-requirements.txt"

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`

Install neca

You can follow instructions from : https://www.mersenneforum.org/showthread.php?t=23087

Todo (aka. Help wanted !)

Implement test method in each attack
Assign the correct speed value in each attack

zi3n/RsaCtfTool