Description
Given two l-isogenous elliptic curves, a well-known algorithm of Elkies uses modular polynomials to compute this isogeny explicitly. In this work, we generalize his ideas to Jacobians of genus 2 curves. Our algorithms works for both l-isogenies and (in the RM case) cyclic isogenies, and uses Siegel or Hilbert type modular equations respectively. This has applications for point counting in genus 2: SEA-style methods are now available.<br/> lien: http://desktop.visio.renater.fr/scopia?ID=726145***4969&autojoin
Prochains exposés
-
Key Attack on the ACDGV Matrix Encryption Scheme
Orateur : Anmoal Porwal - Technical University of Munich
I will present our key-recovery attack on the ACDGV public-key encryption scheme proposed at ASIACRYPT 2024 by Aragon, Couvreur, Dyseryn, Gaborit, and Vinçotte. The secret key is a Gabidulin code hidden by appending random rows and columns and by left- and right-multiplication with invertible matrices. Our attack exploits the resulting algebraic structure to recover an equivalent secret key. It[…]-
Cryptography
-
Asymmetric primitive
-
-
Module Learning With Errors and Structured Extrapolated Dihedral Cosets
Orateur : Jinwei Zheng - Télécom Paris
The Module Learning With Errors (MLWE) problem is the fundamental hardness assumption underlying the key encapsulation and signature schemes ML-KEM and ML-DSA, which have been selected by NIST for post-quantum cryptography standardization. Understanding its quantum hardness is crucial for assessing the security of these standardized schemes. Inspired by the equivalence between LWE and[…]-
Cryptography
-
-
European Cyber Week: atelier cryptographie post-quantique
Dans la continuité des éditions 2021, 2022 et 2024, la DGA — en partenariat avec CREACH LABS et avec le soutien de l'ANSSI, de l'IRISA, de l'IRMAR et du Pôle d'Excellence Cyber — organise la 4e édition de l'atelier consacré à la cryptographie post-quantique dans le cadre de l'European Cyber Week 2026. Attention, il faut s'inscrire (gratuitement) au préalable — s'inscrire à la conférence Les[…] -
Journée post-quantique du séminaire crypto
Journée scientifique sur la cryptographie post-quantique dans la foulée de l'European Cyber Week avec des exposés plus techniques que ceux de l'ECW.