Exploiting the leakage: Analysis of some authenticated encryption schemes

Abstract

The ongoing CAESAR competition, aimed at finding robust and secure authenticated encryption schemes provides many new submissions for analysis. We analyzed many schemes and came across a plenitude of techniques, design ideals and security notions. In view of the above, we present key recovery attacks using DPA for Deoxys, Joltik and ELmD, and a forgery attack on AEGIS. In our analysis of the various schemes, we found out that, schemes using Sponge constructions with pre-initialized keys such as Ascon, ICEPOLE, Keyak, NORX, PRIMATEs, etc. were significantly harder to attack than contemporary designs using standard building blocks from a side channel perspective. We also implement and demonstrate an attack on Joltik-BC, to recover the key in roughly 50–60 traces.