511 results

  • 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[…]
  • ECDSA White-Box Implementations, Feedback on CHES 2021 WhibOx Contest

    • September 29, 2023

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

    Speaker : Agathe Houzelot - Idemia

    Cryptographic algorithms are primarily designed to be secure in the black-box model, where an attacker can only observe their input/output behavior. However in practice, algorithms are rarely executed in a completely isolated environment and additional information is often leaked. In the context of mobile applications or connected objects, devices often lack secure storage to protect secret keys,[…]
  • Generic Attack on Duplex-Bases AEAD Modes using Random Function Statistics

    • September 22, 2023

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

    Speaker : Rachelle Heim Boissier - Inria

    Duplex-based authenticated encryption modes with a sufficiently large key length are proven to be secure up to the birthday bound 2^(c/2), where c is the capacity. However this bound is not known to be tight and the complexity of the best known generic attack, which is based on multicollisions, is much larger: it reaches 2^c/α where α represents a small security loss factor. There is thus an[…]
  • Elliptic curves for SNARKs

    • September 01, 2022

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

    Speaker : Youssef El Housni - LIX

    At CANS’20, El Housni and Guillevic introduced a new 2-chain of pairing-friendly elliptic curves for recursive zero-knowledge Succinct Non-interactive ARguments of Knowledge (zk-SNARKs) made of the former BLS12-377 curve (a Barreto–Lynn–Scott curve over a 377- bit prime field) and the new BW6-761 curve (a Brezing–Weng curve of embedding degree 6 over a 761-bit prime field). First we generalise the[…]
  • Fault tolerant algorithms via decoding: Interleaving techniques

    • June 17, 2022

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

    Speaker : Eleonora Guerrini - Université Montpellier

    Evaluation Interpolation algorithms are a key tool for the algebraic decoding of a large class of codes, including the famous Reed Solomon codes. Recent techniques allow the use of this type of decoding in the more general setting of fault tolerant algorithms, where one has to interpolate erroneous data (potentially computed by an untrusted entity). In this talk we will present algorithms to[…]
  • Soutenance de thèse: Algebraic Cryptanalysis of the Shortest Vector Problem in Ideal Lattices

    • June 13, 2022

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

    Speaker : Olivier Bernard - Rennes