Fault Attacks on Public‐key Cryptographic Algorithms
Michael Tunstall, Guillaume Barbu · 2025
The security of public-key cryptographic algorithms relies on the complexity of well-established mathematical problems. RSA was the first public key cryptographic algorithm to appear in the literature, and is still widely used. The discussion of fault attacks in the academic literature proposed a variety of methods for attacking public key cryptographic algorithms. The first fault attack targeting public-key cryptography, sometimes referred to as the “Bellcore” attack, targets an RSA implementation using the Chinese remainder theorem. When designing countermeasures, we should also make sure that the countermeasure does not introduce additional weaknesses. Obviously, a countermeasure against fault attacks should not introduce a new fault attack path. But it should also avoid the manipulation of sensitive variables that could be used in a side-channel attack. The verification step protects the algorithm from returning a faulty signature that can jeopardize the confidentiality of the secret key.