At CHES 2008, Vigilant proposed an efficient way of implementing a CRT-RSA resistant against Fault Analysis. In this paper, we investigate the fault-resistance of this scheme and we show that it is not immune to fault injection. Indeed, we highlight two weaknesses which can lead an attacker to recover the whole private key by using only one faulty signature. We also suggest some modifications with a negligible cost to improve the fault-resistance of Vigilant's scheme. Therefore the scheme including modifications remains suited to embedded device constraints.

In addition to its usual complexity assumptions, cryptography silently assumes that information can be physically protected in a single location. As one can easily imagine, real-life devices are not ideal and information may leak through different physical channels.This paper gives a rigorous definition of leakage immunity and presents several leakage detection tests. In these tests, failure confirms the probable existence of secret-correlated emanations and indicates how likely the leakage is. Success does not refute the existence of emanations but indicates that significant emanations were not detected on the strength of the evidence presented , which of course, leaves the door open to reconsider the situation if further evidence comes to hand at a later date.