crypto-attacks

name	crypto-attacks
description	Cryptography attack techniques — RSA, ECC, symmetric ciphers, hash collisions, PRNG attacks, lattice/LWE. Use when the challenge involves encryption, decryption, key recovery, nonce reuse, padding oracles, or cryptanalysis of custom schemes.
license	MIT
compatibility	Requires filesystem-based agent with Python 3, SageMath, pycryptodome, and gmpy2.
allowed-tools	Bash Read Write Edit Glob Grep WebSearch
metadata	{"user-invocable":"true","argument-hint":"<crypto-type or ciphertext>"}

Cryptography Attacks

Triage

# Check properties of provided parameters
n = ...  # modulus
e = ...  # public exponent
# Is n factorable? Check FactorDB, sympy.factorint
# Is e small (3)? Try integer root
# Is e large (close to n)? Try Wiener
# Multiple ciphertexts same n? Common modulus
# Multiple n values? Check gcd(n_i, n_j) for shared primes

Document Map

Signal	Document
RSA (n, e, c), textbook RSA, signature oracle	RSA Attacks
ECC parameters, small subgroup, anomalous curve	ECC Attacks
AES-CBC/CTR/GCM, padding oracle, nonce reuse	Symmetric Ciphers
MD5/SHA-1/SHA-256, hash extension, collisions	Hash
MT19937, LCG, XorShift, C rand(), Java Random	PRNG Attacks
Lattice reduction, LWE, HNP, knapsack, subset-sum	Lattice & LWE

Common Attack Checklist

• Factor modulus (FactorDB, YAFU, sympy.factorint)
• Check for trivial small-e (cube root attack if m^e < n)
• Check for common modulus (same n, different e)
• Check for shared primes across multiple n values (batch GCD)
• Check CBC padding oracle if decryption oracle exists
• Check for nonce reuse in CTR/GCM
• Check for hash length extension if H(secret || data) pattern
• Check MT19937 predictability if any PRNG output is observed

Quick Tools

# RSA
python -c "from Crypto.Util.number import *; print(long_to_bytes(int(gmpy2.iroot(c, e)[0])))"
# FactorDB lookup
curl -s "http://factordb.com/api?query=$n"
# Wiener attack
python -c "from owiener import attack; print(attack(e, n))"