David Naccache

Naccache spent the 1990s and early 2000s at Gemplus, then the world's largest smart card maker, where cryptography had to fit into a few kilobytes and survive someone measuring the power draw. That environment made him one of the early names in fault attacks and side channels on cards.

With Jacques Stern he designed the Naccache–Stern cryptosystem in 1998, a homomorphic scheme in the same family as RSA. A year later, with Coron and Stern, he showed that ISO 9796-2 signatures could be forged, forcing a revision of the standard. He later became a professor at ENS and serves as a technical expert in French courts — cryptography as forensics.