Attacking RSA-CRT Signatures with Faults on Montgomery Multiplication.
Pierre-Alain Fouque, Nicolas Guillermin, Delphine Leresteux, Mehdi Tibouchi, Jean-Christophe Zapalowicz · IACR Cryptology ePrint Archive · 2012
In this paper, we present several efficient fault attacks against implementations of RSA–CRT signatures that use modular exponentiation algorithms based on Montgomery multiplication. They apply to any padding function, including randomized paddings, and as such are the first fault attacks effective against RSA–PSS. The new attacks work provided that a small register can be forced to either zero, or a constant value, or a value with zero high-order bits. We show that these models are quite realistic, as such faults can be achieved against many proposed hardware designs for RSA signatures.