Paper 2025/1495
Pairwise independence of AES-like block ciphers
Abstract
We show that $4r + 4$ rounds of a variant of the AES with independent and uniform random round keys are $\varepsilon$-pairwise independent with $\varepsilon = 2^{14}\, 2^{-30r}$. We deduce this bound from a two-norm version of pairwise-independence for SHARK-type ciphers based on the third-largest singular value of the difference-distribution table of the S-box. This approach was worked out in the master thesis of Immo Schütt. Our bounds leave room for improvement, both in the constant prefactor $2^{14}$ — due to a rough conversion between norms — and in the exponent. These improvements will be worked out in an extended version of this note.
Metadata
- Available format(s)
-
PDF
- Category
- Secret-key cryptography
- Publication info
- Preprint.
- Keywords
- Pairwise independenceAESSHARKTruncated differentials
- Contact author(s)
-
tim beyne @ esat kuleuven be
gregor leander @ rub de
immo schuett @ ruhr-uni-bochum de - History
- 2025-09-17: last of 2 revisions
- 2025-08-19: received
- See all versions
- Short URL
- https://ia.cr/2025/1495
- License
-
CC BY
BibTeX
@misc{cryptoeprint:2025/1495,
author = {Tim Beyne and Gregor Leander and Immo Schütt},
title = {Pairwise independence of {AES}-like block ciphers},
howpublished = {Cryptology {ePrint} Archive, Paper 2025/1495},
year = {2025},
url = {https://eprint.iacr.org/2025/1495}
}