Paper 2020/244 Original: eprint.iacr.org/2020/244 ↗
On Adaptive Attacks against Jao-Urbanik’s Isogeny-Based Protocol
Abstract
The k-SIDH protocol is a static-static isogeny-based key agreement protocol. At Mathcrypt 2018, Jao and Urbanik introduced a variant of this protocol which uses non-scalar automorphisms of special elliptic curves to improve its efficiency. In this paper, we provide a new adaptive attack on Jao-Urbanik's protocol. The attack is a non-trivial adaptation of Galbraith-Petit-Shani-Ti's attack on SIDH (Asiacrypt 2016) and its extension to k-SIDH by Dobson-Galbraith-LeGrow-Ti-Zobernig (IACR eprint 2019). Our attack provides a speedup compared to a naïve application of Dobson et al.'s attack to Jao-Urbanik's scheme, exploiting its inherent structure. Estimating the security of k-SIDH and Jao-Urbanik's variant with respect to these attacks, k-SIDH provides better efficiency.
Metadata
- Available format(s)
PDF- Category
- Public-key cryptography
- Publication info
- Preprint.
- History
- 2020-04-30: last updated
- 2020-02-25: published
- Short URL
- https://ia.cr/2020/244
- License
- https://creativecommons.org/licenses/by/4.0/
BibTeX
@misc{cryptoeprint:2020/244,
author = {Andrea Basso and Péter Kutas and Simon-Philipp Merz and Christophe Petit and Charlotte Weitkämper},
title = {On Adaptive Attacks against Jao-Urbanik’s Isogeny-Based Protocol},
howpublished = {Cryptology {ePrint} Archive, Paper 2020/244},
year = {2020},
url = {https://eprint.iacr.org/2020/244}
}