Multiple Impossible Differential Cryptanalysis on Reduced FOX

Xinran LI  Fang-Wei FU  Xuan GUANG  

IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences   Vol.E98-A   No.3   pp.906-911
Publication Date: 2015/03/01
Online ISSN: 1745-1337
DOI: 10.1587/transfun.E98.A.906
Type of Manuscript: LETTER
Category: Cryptography and Information Security
FOX block cipher,  cryptanalysis,  multiple impossible differential,  the early abort technique,  

Full Text: PDF(219.7KB)>>
Buy this Article

FOX is a family of block ciphers published in 2004 and is famous for its provable security to cryptanalysis. In this paper, we present multiple 4-round impossible differentials and several new results of impossible differential attacks on 5,6,7-round FOX64 and 5-round FOX128 with the multiple differentials and the new early abort technique which shall reduce the data complexity and the time complexity respectively. In terms of the data complexity and the time complexity, our results are better than any of the previously known attacks.