Fast software encryption attacks on AES

Abstract

In this work, we compare different faster than brute-force single-key attacks on the full AES in software. Contrary to dedicated hardware implementations, software implementations are more transparent and do not over-optimize a specific type of attack. We have analyzed and implemented a black-box brute-force attack, an optimized brute-force attack and a biclique attack on AES-128. Note that all attacks perform an exhaustive key search but the latter two do not need to recompute the whole cipher for all keys. To provide a fair comparison, we use CPUs with Intel AES-NI since these instructions tend to favor the generic black-box brute-force attack. Nevertheless, we are able to show that on Sandy Bridge the biclique attack on AES-128 is 17% faster, and the optimized brute-force attack is 3% faster than the black-box brute-force attack. © 2013 Springer-Verlag Berlin Heidelberg.