Impossible Differential Cryptanalysis of Reduced-Round SKINNY

  • Mohamed Tolba
  • Ahmed Abdelkhalek
  • Amr M. YoussefEmail author
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 10239)


SKINNY is a new lightweight tweakable block cipher family proposed by Beierle et al. at CRYPTO 2016. SKINNY has 6 main variants where SKINNY-n-t is a block cipher that operates on n-bit blocks using t-bit tweakey (key and tweak) where \(n=64\) or 128 and \(t=n\), 2n, or 3n. In this paper, we present impossible differential attacks against reduced-round versions of all the 6 members of the SKINNY family in the single-tweakey model. More precisely, using an 11-round impossible differential distinguisher, we present impossible differential attacks against 18-round SKINNY-n-n, 20-round SKINNY-n-2n and 22-round SKINNY-n-3n (\(n=64\) or 128). To the best of our knowledge, these are the best attacks against these 6 variants in the single-tweakey model.


Cryptanalysis Impossible differential attacks Tweakable Block ciphers SKINNY 


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Copyright information

© Springer International Publishing AG 2017

Authors and Affiliations

  • Mohamed Tolba
    • 1
  • Ahmed Abdelkhalek
    • 1
  • Amr M. Youssef
    • 1
    Email author
  1. 1.Concordia Institute for Information Systems EngineeringConcordia UniversityMontréalCanada

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