On the Joint Security of Encryption and Signature in EMV

We provide an analysis of current and future algorithms for signature and encryption in the EMV standards in the case where a single key-pair is used for both signature and encryption. We give a theoretical attack for EMV’s current RSA-based algorithms, showing how access to a partial decryption oracle can be used to forge a signature on a freely chosen message. We show how the attack might be integrated into EMV’s CDA protocol flow, enabling an attacker with a wedge device to complete an offline transaction without knowing the cardholder’s PIN. Finally, the elliptic curve signature and encryption algorithms that are likely to be adopted in a forthcoming version of the EMV standards are analyzed in the single key-pair setting, and shown to be secure.

• Type: Journal
• Year: 2012
• Where: CTRSA
• Authors: Jean Paul Degabriele, Anja Lehmann, Kenneth G. Paterson, Nigel P. Smart, Mario Strefler
• Keywords: Cryptology, CTRSA 2012, Elliptic Curve, Encryption Algorithms, Forthcoming Version