FortifyIQ, Inc. will present groundbreaking work titled “First Full-fledged Side Channel Attack on HMAC-SHA-2” at Constructive Side-Channel Analysis and Secure Design (COSADE) 2021. FortifyIQ is proud to be a Gold Sponsor at this event.
Side-channel attacks pose a threat to cryptographic algorithms. Hash functions, those from the SHA-2 family, can also be an interesting target if some of their inputs are secret. HMAC is an important use case of a hash function, in which the input is partially secret and thus unknown to the attacker. Despite a few publications that discuss applications of power analysis techniques to attack HMAC-SHA-2, no method has ever demonstrated a full attack on its hardware implementation until now. FortifyIQ presents a novel practical template attack on HMAC-SHA-2, intended primarily against its implementations in hardware. FortifyIQ’s pre-silicon tools took less than two hours, including the profiling and attack stages, to discover the key derivatives that allow forging of HMAC signatures.
The eleventh annual COSADE will be held in Lugano, Switzerland, and online October 25–27, 2021.
COSADE’s program committee is comprised of security experts from organizations including Rambus, Infineon, Microsoft Research, STMicroelectronics, and universities such as the University of Adelaide (AU), TU Darmstadt (DE), Yale University (US), and the University of Bristol (UK), among others. The COSADE program committee selected FortifyIQ’s paper titled “First Full-fledged Side Channel Attack on HMAC-SHA-2.”
The COSADE program committee stated:
“Generic power analysis attacks on HMAC-SHA-2 are non-trivial due to the complexity of intermediate result mixing. Thus, previous work in the area were ‘full’ attacks, but often exploited artifacts of usage or implementation to simplify the attack design. This meant the previous work was not directly applicable to other implementations or usages.
By comparison, this paper explores a ‘full’ power analysis attack of an open-source HMAC-SHA-256 hardware implementation being used in a generic setting. This means it is applicable to almost all usages of HMAC-SHA-256 and represents a useful research contribution, even to show that the algorithm is fundamentally attackable.
The background—including showing the algorithm and leakage—is excellent and helps this paper serve as a one-stop reference for demonstrating leakage potential, which is valuable for those working on countermeasures.”
