Description
For many mutli-party applications group signatures are important cryptographic primitives that can be used for the purpose of anonymity and privacy. In classical group signatures members of a group are able to sign messages anonymously on behalf of the group. However, there exists a designated authority, called group manager, that initializes the scheme, adds new group members, and is able to open group signatures, i.e., identify the signer. Obviously, in classical group signatures the group manager is given enormous power compared to other group members and is required to be trusted to act as predestinated. On the other hand there exist multi-party applications where such centralized control (trust) is undesirable, e.g., federated (democratic) systems. For this kind of applications it is desirable to have a group signature scheme which provides similar properties but is independent of any centralized control.
Prochains exposés
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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
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Asymmetric primitive
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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
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