Zero-correlation linear attack on reduced-round SKINNY

At ToSC 2019,Ankele et al.proposed a novel idea for constructing zero-correlation linear distinguishers in a related-tweakey model.This paper further clarifies this principle and gives a search model for zero-correlation distin-guishers.As a result,for the first time,the authors construct 14-round and 16-round zero-correlation linear distinguishers for SKINNY-n-2n and SKINNY-n-3n,respectively,which are both two rounds longer than Anekele et al.'s.Based on these distinguishers,the paper presents related-tweakey zero-correlation linear attacks on 21-round SKINNY-n-2n and 25-round SKINNY-n-3n,respectively.