Séminaire de Brice Colombier, Laboratoire H. Curien (SESAM)
Physical Security of Code-based Cryptosystems based on the Syndrome Decoding Problem
Code-based cryptosystems gained a lot of attention in the past few years thanks to the NIST post-quantum cryptography standardization process. After BIKE, Classic McEliece and HQC have been selected for the fourth round, an important aspect to consider is the strength of their implementations against physical attacks, both side-channel and fault injection attacks. In this presentation, we focus on the Classic McEliece cryptosystem. After detailing the new theoretical framework of the so-called "integer syndrome decoding problem", we give two examples of physical attacks that allow an attacker to place himself in this framework, by targeting the syndrome computation step : the first one by laser fault injection, the second one by observing the power consumption of the device. Then, we provide two methods that allow to recover the message, starting with a faulty syndrome in N. The first one is based on generic integer programming techniques, while the second one is more specific and much more computationally efficient.
Vincent Grosso du Laboratoire H. Curien (SESAM) sera également présent lors de ce séminaire et fera une présentation le 22 février 2024.