Paper 2023/755
The security of Kyber's FO-transform
, Eindhoven University of TechnologyAbstract
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.
- Keywords
- Post-quantum cryptographyKyberCrystalsKey-Encapsulation MechanismKEMFujisaki-Okamoto TransformFOQROM
- Contact author(s)
-
mbb @ fc up pt
andreas @ huelsing net - History
- 2023-05-25: approved
- 2023-05-25: received
- See all versions
- Short URL
- https://ia.cr/2023/755
- License
-
CC BY
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},
note = {\url{https://eprint.iacr.org/2023/755}},
url = {https://eprint.iacr.org/2023/755}
}
