cryptoProhard

RBG+

kalmarctf

Task: RSA with LCG exponents, outputs are integer sums of consecutive ciphertexts c_i + c_{i+1}. Solution: polynomial GCD to recover c_0, then extended GCD on coprime exponents to recover message without factoring N.

$ ls tags/ techniques/
rsalcgpolynomial_gcdrevenge_challengeinteger_sum_leak
lcg_exponent_recurrencepolynomial_gcd_over_znextended_gcd_message_recoverycoprime_exponent_attack
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