New Observations on Invariant Subspace Attack

Yunwen Liu; Vincent Rijmen

Paper 2017/278

New Observations on Invariant Subspace Attack

Yunwen Liu and Vincent Rijmen

Abstract

Invariant subspace attack is a novel cryptanalytic technique which breaks several recently proposed lightweight block ciphers. In this paper, we propose a new method to bound the dimension of some invariant subspaces in a class of lightweight block ciphers which have a similar structure as the AES but with 4-bit Sboxes. With assumptions on the diffusion layer, the dimension of any invariant subspaces is at most 32 when the inputs into each Sboxes are linearly independent. The observation brings new insights about the invariant subspace attack, as well as lightweight countermeasures to enhance the resistance against it.

Metadata

Available format(s): PDF
Category: Secret-key cryptography
Publication info: Preprint.
Keywords: Invariant subspace attack AES-like Lightweight block ciphers
Contact author(s): yunwen liu @ esat kuleuven be
History: 2017-03-27: received
Short URL: https://ia.cr/2017/278
License: CC BY

BibTeX

@misc{cryptoeprint:2017/278,
      author = {Yunwen Liu and Vincent Rijmen},
      title = {New Observations on Invariant Subspace Attack},
      howpublished = {Cryptology {ePrint} Archive, Paper 2017/278},
      year = {2017},
      url = {https://eprint.iacr.org/2017/278}
}