A fault-injection attack on Fiat-Shamir cryptosystems

Fault-injection attacks and cryptanalysis is a realistic threat for systems implementing cryptographic algorithms. We revisit the fault-injection attacks on the Fiat-Shamir authentication scheme, a popular authentication scheme for service providers like pay per view television, video distribution and cellular phones. We present a new and effective attack on cryptosystems that implement the Fiat-Shamir identification scheme. The attack is successful against all system configurations in contrast to the original Bellcore attack, which has been proven incomplete (easy to defend against).