Paper 2019/909 Original: eprint.iacr.org/2019/909 ↗
A Practicable Timing Attack Against HQC and its Countermeasure
Abstract
In this paper, we present a practicable chosen ciphertext timing attack retrieving the secret key of HQC. The attack exploits a correlation between the weight of the error to be decoded and the running time of the decoding algorithm of BCH codes. For the 128-bit security parameters of HQC, the attack runs in less than a minute on a desktop computer using 5441 decoding requests and has a success probability of approximately 93 percent. To prevent this attack, we propose a constant time algorithm for the decoding of BCH codes. Our implementation of the countermeasure achieves a constant time execution of the decoding process without a significant performance penalty.
Metadata
- Available format(s)
PDF- Category
- Public-key cryptography
- Publication info
- Preprint.
- History
- 2019-09-23: last updated
- 2019-08-08: published
- Short URL
- https://ia.cr/2019/909
- License
- https://creativecommons.org/licenses/by/4.0/
BibTeX
@misc{cryptoeprint:2019/909,
author = {Guillaume Wafo-Tapa and Slim Bettaieb and Loic Bidoux and Philippe Gaborit and Etienne Marcatel},
title = {A Practicable Timing Attack Against HQC and its Countermeasure},
howpublished = {Cryptology {ePrint} Archive, Paper 2019/909},
year = {2019},
url = {https://eprint.iacr.org/2019/909}
}