Filter by content type

Select one or more filters. This choice will reload the page to display the filtered results.

Remove all filters

627 results

    • Seminar

    • Cryptography

    How fast do you heal? A taxonomy for post-compromise security in secure-channel establishment.

    • November 10, 2023

    • IRMAR - Université de Rennes - Campus Beaulieu Bat. 22, RDC, Rennes - Amphi Lebesgue

    Speaker : Léo Robert - Université d'Amiens

    Post-Compromise Security (PCS) is a property of secure-channel establishment schemes, which limits the security breach of an adversary that has compromised one of the endpoint to a certain number of messages, after which the channel heals. An attractive property, especially in view of Snowden's revelation of mass-surveillance, PCS features in prominent messaging protocols such as Signal. In this[…]
    • Seminar

    • Cryptography

    SCA-LDPC: A Code-Based Framework for Key-Recovery Side-Channel Attacks on Post-Quantum Encryption Schemes

    • June 14, 2024

    • IRMAR - Université de Rennes - Campus Beaulieu Bat. 22, RDC, Rennes - Amphi Lebesgue

    Speaker : Denis Nabokov - Université de Lund

    Whereas theoretical attacks on standardized crypto primitives rarely lead to actual practical attacks, the situation is different for side-channel attacks. Improvements in the performance of side-channel attacks are of utmost importance. In this paper, we propose a framework to be used in key-recovery side-channel attacks on CCA-secure post-quantum encryption schemes. The basic idea is to[…]
    • Seminar

    • Cryptography

    Shorter Lattice-Based Fiat-Shamir Signatures

    • January 26, 2024

    • IRMAR - Université de Rennes - Campus Beaulieu Bat. 22, RDC, Rennes - Amphi Lebesgue

    Speaker : Julien Devevey - ANSSI

    We present HAETAE (Hyperball bimodAl modulE rejecTion signAture schemE), a new lattice-based signature scheme, which we submitted to the Korean Post-Quantum Cryptography Competition for standardization. Like the NIST-selected Dilithium signature scheme, HAETAE is based on the Fiat-Shamir with Aborts paradigm, but our design choices target an improved complexity/compactness compromise that is[…]
    • Seminar

    • Cryptography

    Ind-cpa-d insecurity of approximate and exact homomorphic encryption schemes

    • March 29, 2024

    • IRMAR - Université de Rennes - Campus Beaulieu Bat. 22, RDC, Rennes - Amphi Lebesgue

    Speaker : Elias Suvanto - Cryptolab

    Fully Homomorphic Encryption enables the evaluation of arbitrary circuits over encrypted data while maintaining the confidentiality of the underlying messages. It greatly enhances functionality but also comes with security challenges for some applications like Threshold FHE. While the standard IND-CPA security is sufficient against honest but curious adversaries, a stronger security notion called[…]
    • Seminar

    • Cryptography

    An extension of Overbeck’s attack with an application to cryptanalysis of Twisted Gabidulin-based schemes.

    • October 06, 2023

    • IRMAR - Université de Rennes - Campus Beaulieu Bat. 22, RDC, Rennes - Amphi Lebesgue

    Speaker : Ilaria Zappatore - XLIM

    In this talk, I will discuss the decoding of Gabidulin and related codes from a cryptographic point of view, pointing out that these codes can be decoded solely from the knowledge of a generator matrix. I will also present an extension of Gibson and Overbeck attacks on the generalized GPT encryption scheme (instantiated with the Gabidulin code) for different ranks of the distortion matrix. Finally[…]
    • Seminar

    • Cryptography

    Side channel analysis against AEAD lightweight cryptography

    • May 24, 2024

    • IRMAR - Université de Rennes - Campus Beaulieu Bat. 22, RDC, Rennes - Amphi Lebesgue

    Speaker : Modou SARRY - IMT Atlantique

    Les dispositifs interconnectés tels que les réseaux de capteurs, la santé, les systèmes de contrôle distribués, l’internet des objets et les systèmes cyber-physiques sont de plus en plus répandus. Cette transition vers de petits appareils engendre de nouvelles préoccupations en matière de sécurité et de vie privée, car de nombreux algorithmes cryptographiques classiques ne répondent pas toujours[…]