1. Attacks on Secure Logging Schemes 2017 FinancialCryptography TamperResistance fc17.ifca.ai
    Gunnar Hartung

    We present four attacks on three cryptographic schemes in-tended for securing log files against illicit retroactive modification. Our first two attacks regard the LogFAS scheme by Yavuz et al. (FinancialCryptography 2012), whereas our third and fourth attacks break the BM-and AR-FssAgg schemes by Ma (AsiaCCS 2008).All schemes have an accompanying security proof, seemingly contradicting the existence of attacks. We point out flaws in these proofs, resolvingthe contradiction.