Skip to main content

common_modulus_attack

logicaffeine_proof::factor

Function common_modulus_attack 

Source 
pub fn common_modulus_attack(
    e1: &BigInt,
    e2: &BigInt,
    c1: &BigInt,
    c2: &BigInt,
    n: &BigInt,
) -> Option<BigInt>
Expand description

Common-modulus attack: recover m when the SAME message is sent to the same modulus N under two coprime public exponents e₁, e₂ (a key-reuse mistake). Bézout gives a·e₁ + b·e₂ = 1, so c₁ᵃ · c₂ᵇ = m^{a·e₁ + b·e₂} = m (mod N) — negative exponents handled by inverting the ciphertext.