International Association for Cryptologic Research (IACR)
Abstract
The all-subkeys recovery (ASR) attack is an extension of the meet-in-the-middle
attack, which allows evaluating the security of a block cipher without analyzing its key
scheduling function. Combining the ASR attack with some advanced techniques such as the
function reduction and the repetitive ASR attack, we show the improved ASR attacks on the
7-round reduced FOX64 and FOX128. Moreover, the improved ASR attacks on the 119-, 105-
and 99-round reduced KATAN32, KATAN48 and KATAN64, and the 42-round reduced SHACAL-2
are also presented, respectively. As far as we know, all of those attacks are the best single-key
attacks with respect to the number of attacked rounds in literature
