Paper 2013/336

A Novel Technique in Linear Cryptanalysis

Wen-Long Sun Jie Guan Lin Ding

Abstract

In this paper, we focus on a novel technique called cube-linear attack, which is obtained by combining the cube and linear attacks together, is first proposed to deal with the probabilistic polynomial, aiming to furthermore mine the available secret information. Based on different combination ways of the two attacks, moreover, two cube-linear schemes are discussed. Naturally, we can use cube-linear attack as an unordinary trick in linear cryptanalysis, which has never been considered by the previous linear cryptanalysis yet. As a new contribution to linear cryptanalysis, it is beneficial to allow for a reduction in the amount of data required for a successful attack in specific circumstances. Applying our method to a reduced-round Trivium, as an example, we get better linear cryptanalysis results. More importantly, we believe that the novel linear cryptanalysis technique introduced in this paper can be extended to other ciphers. In other words, it is worth considering for our method in linear cryptanalysis.