SQIsign2D–West: The Fast, the Small, and the Safer

A Basso, P Dartois, LD Feo, A Leroux, L Maino… - … Conference on the …, 2024 - Springer
Abstract We introduce SQIsign2D–West, a variant of SQIsign using two-dimensional isogeny
representations. SQIsignHD introduced four-and eight-dimensional isogeny representations …

SCALLOP-HD: group action from 2-dimensional isogenies

M Chen, A Leroux, L Panny - IACR International Conference on Public …, 2024 - Springer
We present SCALLOP-HD, a novel group action that builds upon the recent SCALLOP
group action introduced by De Feo, Fouotsa, Kutas, Leroux, Merz, Panny and Wesolowski in …

Hidden stabilizers, the isogeny to endomorphism ring problem and the cryptanalysis of pSIDH

M Chen, M Imran, G Ivanyos, P Kutas, A Leroux… - … Conference on the …, 2023 - Springer
Abstract The Isogeny to Endomorphism Ring Problem (IsERP) asks to compute the
endomorphism ring of the codomain of an isogeny between supersingular curves in …

Deuring for the People: Supersingular Elliptic Curves with Prescribed Endomorphism Ring in General Characteristic.

JK Eriksen, L Panny, J Sotáková, M Veroni - IACR Cryptol. ePrint Arch., 2023 - ams.org
Constructing a supersingular elliptic curve whose endomorphism ring is isomorphic to a
given quaternion maximal order (one direction of the Deuring correspondence) is known to …

Verifiable random function from the Deuring correspondence and higher dimensional isogenies

A Leroux - 2023 - hal.science
In this paper, we introduce the family DeuringVRF y, z of Verifiable Random Function (VRF)
protocols. Based on isogenies between supersingular curves, the random function at the …

Breaking and repairing SQIsign2D-East

W Castryck, M Chen, R Invernizzi, G Lorenzon… - Cryptology ePrint …, 2024 - eprint.iacr.org
We present a key recovery attack on SQIsign2D-East that reduces its security level from
$\lambda $ to $\lambda/2$. We exploit the fact that each signature leaks a Legendre symbol …

Computation of Hilbert class polynomials and modular polynomials from supersingular elliptic curves

A Leroux - arXiv preprint arXiv:2301.08531, 2023 - arxiv.org
We present several new heuristic algorithms to compute class polynomials and modular
polynomials modulo a prime $ p $ by revisiting the idea of working with supersingular elliptic …

SQIPrime: A dimension 2 variant of SQISignHD with non-smooth challenge isogenies

M Duparc, TB Fouotsa - International Conference on the Theory and …, 2024 - Springer
We introduce SQIPrime, a post-quantum digital signature scheme based on the Deuring
correspondence and Kani's Lemma. Compared to its predecessors that are SQISign and …

Avoiding Trusted Setup in Isogeny-based Commitments

GT Saah, TB Fouotsa, E Fouotsa… - Cryptology ePrint …, 2024 - eprint.iacr.org
In 2021, Sterner proposed a commitment scheme based on supersingular isogenies. For
this scheme to be binding, one relies on a trusted party to generate a starting supersingular …

Further Connections Between Isogenies of Supersingular Curves and Bruhat-Tits Trees

S Galbraith, V Gilchrist, S Levin… - Cryptology ePrint …, 2024 - eprint.iacr.org
We further explore the explicit connections between supersingular curve isogenies and
Bruhat-Tits trees. By identifying a supersingular elliptic curve $ E $ over $\mathbb {F} _p $ as …