Meet-in-the-Middle Preimage Attacks on Sponge-Based Hashing

The Meet-in-the-Middle (MitM) attack has been widely applied to preimage attacks on Merkle-Damgård (MD) hashing. In this paper, we introduce a generic framework of the MitM sponge-based We find certain bit conditions can significantly reduce diffusion unknown bits and lead longer characteristics. To good or optimal configurations attacks, e.g., conditions, neutral sets, matching points, bit-level MILP-based automatic tools Keccak, Ascon Xoodyak. scale models make them solvable in reasonable time, series properties targeted hashing are considered modelling, such as linear structure CP-kernel for Boolean expression Sbox Ascon. Finally, give an improved 4-round Keccak-512/SHA3, break nearly 10 years’ cryptanalysis record. also first 3-/4-round Ascon-XOF 3-round Xoodyak-XOF.