Paper 2023/755 Original: eprint.iacr.org/2023/755 ↗
The security of Kyber's FO-transform
Abstract
In this short note we give another direct proof for the variant of the FO transform used by Kyber in the QROM. At PKC'23 Maram & Xagawa gave the first direct proof which does not require the indirection via FO with explicit rejection, thereby avoiding either a non-tight bound, or the necessity to analyze the failure probability in a new setting. However, on the downside their proof produces a bound that incurs an additive collision bound term. We explore a different approach for a direct proof, which results in a simpler argument closer to prior proofs, but a slightly worse bound.
Metadata
- Available format(s)
PDF- Category
- Public-key cryptography
- Publication info
- Preprint.
- History
- 2023-05-25: last updated
- 2023-05-25: published
- Short URL
- https://ia.cr/2023/755
- License
- https://creativecommons.org/licenses/by/4.0/
BibTeX
@misc{cryptoeprint:2023/755,
author = {Manuel Barbosa and Andreas Hülsing},
title = {The security of Kyber's FO-transform},
howpublished = {Cryptology {ePrint} Archive, Paper 2023/755},
year = {2023},
url = {https://eprint.iacr.org/2023/755}
}