Paper 2025/1495 Original: eprint.iacr.org/2025/1495 ↗
Pairwise independence of AES-like block ciphers
Abstract
We prove that $4r + 4$ rounds of an AES variant with independent and uniform random round keys are $\varepsilon$-close to pairwise independent with $\varepsilon = 2^{14}\, 2^{-39r}$. This result follows from a near-optimal bound for a two-norm version of pairwise independence for the Shark construction, depending on the third singular value of the difference-distribution table of the S-boxes. Our analysis combines insights from cryptanalysis — in particular, truncated differentials — and linear algebra over the reals.
Metadata
- Available format(s)
PDF- Category
- Secret-key cryptography
- Publication info
- Preprint.
- History
- 2026-09-27: last updated
- 2025-08-19: published
- Short URL
- https://ia.cr/2025/1495
- License
- https://creativecommons.org/licenses/by/4.0/
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}
}