We propose an improved preimage attack on one-block MD4 with the time complexity 2 MD4 compression function operations, as compared to 2 in [3]. We research the attack procedure in [3] and formulate the complexity for computing a preimage attack on one-block MD4. We attain the result mainly through the following two aspects with the help of the complexity formula. First, we continue to compute ...

A hash function is constructed based on a three-layer neural network. The three neuron-layers are used to realize data confusion, diffusion and compression respectively, and the multi-block hash mode is presented to support the plaintext with variable length. Theoretical analysis and experimental results show that this hash function is one-way, with high key sensitivity and plaintext sensitivit...

This paper presents a new generic technique, named sieve-in-the-middle, which improves meet-in-the-middle attacks in the sense that it provides an attack on a higher number of rounds. Instead of selecting the key candidates by searching for a collision in an intermediate state which can be computed forwards and backwards, we here look for the existence of valid transitions through some middle s...

This paper presents a new generic technique, named sievein-the-middle, which improves meet-in-the-middle attacks in the sense that it provides an attack on a higher number of rounds. Instead of selecting the key candidates by searching for a collision in an intermediate state which can be computed forwards and backwards, we look for the existence of valid transitions through some middle sbox. C...

TWINE is a recent lightweight block cipher based on a Feistel structure. We rst present two new attacks on TWINE-128 reduced to 25 rounds that have a slightly higher overall complexity than the 25round attack presented by Wang and Wu at ACISP 2014, but a lower data complexity. Then, we introduce alternative representations of both the round function of this block cipher and of a sequence of 4 r...