Abstract. We present high probability differential trails on 2 and 3 rounds of BLAKE-32. Using the trails we are able to launch boomerang attacks on up to 8 round-reduced keyed permutation of BLAKE-32. Also, we show that boomerangs can be used as distinguishers for hash/ compression functions and present such distinguishers for the compression function of BLAKE-32 reduced to 7 rounds. Since our distinguishers on up to 6 round-reduced keyed permutation of BLAKE-32 are practical (complexity of only 2 12 encryptions), we are able to find boomerang quartets on a PC.
Furthermore, Biryukov et al. REF presented a boomerang attack on the SHA-3 finalist Blake resulting in a distinguisher for 7 rounds of the Blake-32 compression function with a complexity of 2 232 .
Boomerang Attacks on BLAKE-32
FSE
Mathematics Computer Science