Improved Integral Attacks on SIMON32 and SIMON48 with Dynamic Key-Guessing Techniques

Abstract

Dynamic key-guessing techniques, which exploit the property of AND operation, could improve the differential and linear cryptanalytic results by reducing the number of guessed subkey bits and lead to good cryptanalytic results for SIMON. They have only been applied in differential and linear attacks as far as we know. In this paper, dynamic key-guessing techniques are first introduced in integral cryptanalysis. According to the features of integral cryptanalysis, we extend dynamic key-guessing techniques and get better integral cryptanalysis results than before. As a result, we present integral attacks on 24-round SIMON32, 24-round SIMON48/72, and 25-round SIMON48/96. In terms of the number of attacked rounds, our attack on SIMON32 is better than any previously known attacks, and our attacks on SIMON48 are the same as the best attacks.

Deep Learning-Based Cryptanalysis of Lightweight Block Ciphers

“…e authors in [37] showed differential attacks of up to slightly more than half of the number of rounds for Simon and Speck families of block ciphers. e authors in [38] showed an integral attack on 24-round Simon32/64 with time complexity of 2 63 and the data complexity of 2 32 . e work in [39] showed an improved differential attack on 14-round Speck32/64 with time complexity of 2 63 and the data complexity of 2 31 .…”