Paper 2025/1227 Original: eprint.iacr.org/2025/1227 ↗
Improved Key-recovery Attacks on ARADI
Abstract
ARADI is a low-latency block cipher introduced by the U.S. National Security Agency (NSA), targeting secure and efficient memory encryption. However, unlike most academic cipher proposals, the design rationale behind ARADI has not been made public, leaving its security to be only assessed through independent analysis. In this work, we present improved key-recovery attacks on up to 12 out of 16 rounds of ARADI in the single-key setting — advancing the best known attacks by two rounds. Our techniques build upon the ZeroSum distinguisher framework and leverage the Fast Hadamard Transform (FHT). A central insight in our attacks is that the linear layer of ARADI exhibits weak diffusion. This structural property allows partial decryption with only a subset of the round keys, significantly reducing the key-guessing space.
Metadata
- Available format(s)
PDF- Category
- Attacks and cryptanalysis
- Publication info
- Preprint.
- History
- 2026-01-26: last updated
- 2025-07-02: published
- Short URL
- https://ia.cr/2025/1227
- License
- https://creativecommons.org/licenses/by/4.0/
BibTeX
@misc{cryptoeprint:2025/1227,
author = {Orr Dunkelman and Shibam Ghosh},
title = {Improved Key-recovery Attacks on ARADI},
howpublished = {Cryptology {ePrint} Archive, Paper 2025/1227},
year = {2025},
url = {https://eprint.iacr.org/2025/1227}
}