627 results

  • Soutenance de thèse: Study and design of new encryption primitives based on rank metric error correcting codes

    • December 10, 2021

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

    Speaker : Ba Duc Pham - Rennes

    In 2005, Faure and Loidreau proposed a new rank-metric cryptosystem inspired from the Hamming metric scheme of Augot-Finiasz in 2003. In 2018, it was broken by the attack of Gaborit, Otmani and Kalachi. Recently, there are some attempts of repairing the Faure-Loidreau scheme, for example the work of Renner, Puchinger and Wachter–Zeh which is called LIGA. In this thesis, we also introduce a new[…]
  • PARASITE: PAssword Recovery Attack against Srp Implementations in ThE wild

    • December 03, 2021

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

    Speaker : Daniel De Almeida Braga - Université Rennes 1

    Protocols for password-based authenticated key exchange (PAKE) allow two users sharing only a short, low-entropy password to establish a secure session with a cryptographically strong key. The challenge in designing such protocols is that they must resist offline dictionary attacks in which an attacker exhaustively enumerates the dictionary of likely passwords in an attempt to match the used[…]
  • Quantum cryptanalysis of block ciphers: beyond quadratic speedups

    • November 26, 2021

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

    Speaker : André Schrottenloher - CWI

    The security of modern cryptosystems relies on computational assumptions, which may be challenged by the advent of large-scale quantum computing devices.<br/> While Shor's algorithm is known to break today's most popular public-key schemes, secret-key cryptosystems are generally expected to retain half of their pre-quantum bits of security. However, the precise advantage of quantum attacks cannot[…]
  • Ransomware Detection Using Markov Chain Models Over File Headers

    • November 26, 2021

    • Inria Center of the University of Rennes - - Petri/Turing room

    Speaker : David Lubicz (DGA-MI)

    In this paper, a new approach for the detection of ransomware based on the runtime analysis of their behaviour is presented. The main idea is to get samples by using a mini-filter to intercept write requests, then decide if a sample corresponds to a benign or a malicious write request. To do so, in a learning phase, statistical models of structured file headers are built using Markov chains. Then[…]
  • Formal security proofs in a post-quantum world

    • November 19, 2021

    • Inria Center of the University of Rennes - - Petri/Turing room

    Speaker : Charlie Jacomme (CISPA)

    In the recent years, formals methods for security and their associated tools have been used successfully both to find novel and complex attacks on many protocols [A] and to help in their standardization process. They however face a new challenge with the increasing probability of quantum computers coming into the real-world: we need to be able to provide guarantees against quantum attackers.In[…]
  • A Concrete Treatment of Efficient Continuous Group Key Agreement via Multi-Recipient PKEs

    • November 19, 2021

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

    Speaker : Thomas Prest - PQShield

    Continuous group key agreements (CGKAs) are a class of protocols that can provide strong security guarantees to secure group messaging protocols such as Signal and MLS. Protection against device compromise is provided by commit messages: at a regular rate, each group member may refresh their key material by uploading a commit message, which is then downloaded and processed by all the other members[…]