Improved multi-dimensional Meet in the middle cryptanalysis of KATAN

Abstract

We study multidimensional meet-in-the-middle attacks on
the KATAN block cipher family. Several improvements to the basic

attacks are explained. The most noteworthy of these is the technique of
guessing only non-linearly involved key bits, which reduces the search
space by a significant factor. The optimization decreases the complexity
of multidimensional meet-in-the-middle attacks, allowing more rounds of
KATAN to be efficiently attacked than previously reported.