Linear Cryptanalysis of Reduced-Round Simeck Using Super Rounds

The Simeck family of lightweight block ciphers was proposed by Yang et al. in 2015, which combines the design features NSA-designed Simon and Speck. Previously, we use linear cryptanalysis using super-rounds to increase efficiency implementing Matsui’s second algorithm achieved good results on all variants Simon. improved attacks result from observation that, after four rounds encryption, one bit left half state cipher depends only 17 key bits (19 for larger cipher). We were able follow a similar approach, Simeck, with an improvement 32 48 relaxing previous constraint single active bit, multiple instead. In this paper present against Simeck: 19-rounds 32/64, 28-rounds 48/96, 34-rounds 64/128, often direct recovery full master without repeating attack over rounds. also verified 8, 10, 12 32/64.