In this paper we present a preimage attack on EnRUPT512. We exploit the fact that the internal state is only a little bit larger than the critical security level: 1152 bits against 1024 bits. The absence of a message expansion and a fairly simple compression function allow us to fix the values for some state words and thus reduce the size of birthday state space in the meet-in-the-middle attack...

In this paper, we present improved preimage attacks on the reduced-round GOST hash function family, which serves as the new Russian hash standard, with the aid of techniques such as the rebound attack, the Meet-in-the-Middle preimage attack and the multicollisions. Firstly, the preimage attack on 5-round GOST-256 is proposed which is the first preimage attack for GOST-256 at the hash function l...

Whirlwind is a keyless AES-like hash function that adopts the Sponge model. According to its designers, the function is designed to resist most of the recent cryptanalytic attacks. In this paper, we evaluate the second preimage resistance of theWhirlwind hash function. More precisely, we apply a meet in the middle preimage attack on the compression function which allows us to obtain a 5-round p...

This paper shows preimage attacks against reduced SHA-1 up to 57 steps. The best previous attack has been presented at CRYPTO 2009 and was for 48 steps finding a two-block preimage with incorrect padding at the cost of 2 evaluations of the compression function. For the same variant our attacks find a one-block preimage at 2 and a correctly padded two-block preimage at 2 evaluations of the compr...

In this paper, we propose preimage attacks on 41-step SHA-256 and 46-step SHA-512, which drastically increase the number of attacked steps compared to the best previous preimage attack working for only 24 steps. The time complexity for 41-step SHA-256 is 2 compression function operations and the memory requirement is 2 × 10 words. The time complexity for 46-step SHA-512 is 2 compression functio...

This paper evaluates the preimage resistance of the Tiger hash function. We will propose a pseudo-preimage attack on its compression function up to 23 steps with a complexity of 2, which can be converted to a preimage attack on 23-step Tiger hash function with a complexity of 2. The memory requirement of these attacks is 2 words. Our pseudo-preimage attack on the Tiger compression function adop...

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 ...