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...

As an international standard adopted by ISO/IEC, the block cipher Camellia has been used in various cryptographic applications. In this paper, we reevaluate the security of Camellia against impossible differential cryptanalysis. Specifically, we propose several 7-round impossible differentials with the FL/FL layers. Based on them, we mount impossible differential attacks on 11-round Camellia192...

Impossible differential cryptanalysis is an important tool for evaluating the security level of a block cipher, and the key step of this cryptanalysis is to find the longest impossible differential. This paper focuses on retrieving impossible differentials for m-cell Skipjack-like structure with SP/SPS round function (named SkipjackSP and SkipjackSPS resp.). Up to now, known longest impossible ...

Impossible differential attack is a well-known mean to examine robustness of block ciphers. Using impossible differ- ential cryptanalysis, we analyze security of a family of lightweight block ciphers, named Midori, that are designed considering low energy consumption. Midori state size can be either 64 bits for Midori64 or 128 bits for Midori128; however, both vers...

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...

Impossible differential attacks against Rijndael and Crypton have been proposed up to 5-round. In this paper we expand the impossible differential attacks to 6-round. Although we use the same 4-round impossible differential as in five round attacks, we put this impossible differential in the middle of 6-round. That is, we will consider one round before the impossible differential and one more r...

MISTY1 is a Feistel block cipher that received a great deal of cryptographic attention. Its recursive structure, as well as the added FL layers, have been successful in thwarting various cryptanalytic techniques. The best known attacks on reduced variants of the cipher are on either a 4-round variant with the FL functions, or a 6-round variant without the FL functions (out of the 8 rounds of th...

In this paper, we present more powerful 6-round impossible differentials for large-block Rijndael-224 and Rijndael-256 than the ones used by Zhang et al. in ISC 2008. Using those, we can improve the previous impossible differential cryptanalysis of both 9-round Rijndael224 and Rijndael-256. The improvement can lead to 10-round attack on Rijndael-256 as well. With 2 chosen plaintexts, an attack ...