1 Statistical attacks on block ciphers make use of a property of the cipher so that an incident occurs with different probabilities depending on whether the correct key is used or not. For instance, differential cryptanalysis [1] considers characteristics or differentials which show that a particular output difference should be obtained with a relatively high probability when a particular input...

In this paper, we present several new related-key impossible differential attacks on 7and 8-round AES-192, following the work of Eli Biham and Orr Dunkelman et al. [1]. We choose another relation of the two related keys, start attacks from the very beginning(instead of the third round in [1]) so as to improve the data and time complexities of their attacks. Furthermore, we point out and correct...

In this paper we examine the strength of AES-256 against the related-key impossible differential attack, following the work in [1] and [2]. Firstly, we present a carefully chosen relation between the related keys, which can be extended to 8-round(even more rounds) subkey differences. Then, we construct a 5.5-round related-key impossible differential. Using the differential, we present an attack...

In this paper we examine the strength of AES against the related-key impossible differential attack, following the work of Jakimoski and Desmedt [12]. We use several additional observations to substantially improve the data and time complexities of their attacks. Amongst our results, we present a related-key attack on 7-round AES-192 with data complexity of 2 chosen plaintexts (instead of 2). O...

CLEFIA is a 128-bit block cipher proposed by Sony Corporation in 2007. Our paper introduces a new chosen text attack, the impossible differential-linear attack, on iterated cryptosystems. The attack is efficient for 16-round CLEFIA with whitening keys. In the paper, we construct a 13-round impossible differential-linear distinguisher. Based on the distinguisher, we present an effective attack o...

Serpent is a 128-bit SP-Network block cipher consisting of 32 rounds with variable key length (up to 256 bits long). It was selected as one of the 5 AES finalists. The best known attack so far is a linear attack on an 11-round reduced variant. In this paper we apply the enhanced differential-linear cryptanalysis to Serpent. The resulting attack is the best known attack on 11-round Serpent. It r...

CLEFIA is a 128-bit block cipher proposed by Sony Corporation in 2007. Our paper introduces a new chosen text attack, impossible differential-linear attack, on iterated cryptosystems. The attack is efficient for 16-round CLEFIA with whitening keys. In the paper, we construct a 13-round impossible differential-linear distinguisher. Based on the distinguisher, we present an effective attack on 16...

In this paper, we present a distinguisher for the permutation of SIMD-512 with complexity 2. We extend the attack to a distinguisher for the compression function with complexity 2. The attack is based on the application of the boomerang attack for hash functions. Starting from the middle of the compression function we use techniques from coding theory to search for two differential characterist...

We discuss the security of Message Authentication Code (MAC) schemes from the viewpoint of differential attack, and propose an attack that is effective against DES-MAC and FEAL-MAC. The attack derives the secret authentication key in the chosen plaintext scenario. For example, DES(8-round)-MAC can be broken with 2 pairs of plaintext, while FEAL8-MAC can be broken with 2 pairs. The proposed atta...

In this paper, the impossible differential cryptanalysis is extended to MAC algorithms Pelican, MT-MAC and PC-MAC based on AES and 4-round AES. First, we collect message pairs that produce the inner near-collision with some specific differences by the birthday attack. Then the impossible differential attack on 4-round AES is implemented using a 3-round impossible differential property. For Peli...