Unit
Security and Cryptography Laboratory
LaboratoryRelated publications (856)
Geometric Considerations in Lattice Programming
We provide faster algorithms and fine-grained reductions for lattice problems in general norms. ...
EPFL2023Attacks on some post-quantum cryptographic protocols: The case of the Legendre PRF and SIKE
Post-quantum cryptography is a branch of cryptography which deals with cryptographic algorithms whose hardness assumptions are not based on problems known to be solvable by a quantum computer, such as the RSA problem, factoring or discrete logarithms.This ...
EPFL2022Optimal Symmetric Ratcheting for Secure Communication
Serge Vaudenay, Andrea Felice Caforio, Daniel Patrick Collins, Hailun Yan
To mitigate state exposure threats to long-lived instant messaging sessions, ratcheting was introduced, which is used in practice in protocols like Signal. However, existing ratcheting protocols generally come with a high cost. Recently, Caforio et al. pro ...
OXFORD UNIV PRESS2022Analysis and Improvements of the Sender Keys Protocol for Group Messaging
Messaging between two parties and in the group setting has enjoyed widespread attention both in practice, and, more recently, from the cryptographic community. One of the main challenges in the area is constructing secure (end-to- end encrypted) and effici ...
2022PROFACTORY: Improving IoT Security via Formalized Protocol Customization
Mathias Josef Payer, Fei Wang, Duo Xu, Xiangyu Zhang
As IoT applications gain widespread adoption, it becomes important to design and implement IoT protocols with security. Existing research in protocol security reveals that the majority of disclosed protocol vulnerabilities are caused by incorrectly impleme ...
USENIX ASSOC2022BLOOM: Bimodal Lattice One-out-of-Many Proofs and Applications
We give a construction of an efficient one-out-of-many proof system, in which a prover shows that he knows the pre-image for one element in a set, based on the hardness of lattice problems. The construction employs the recent zero-knowledge framework of Ly ...
SPRINGER INTERNATIONAL PUBLISHING AG2022Verifiable Encodings for Secure Homomorphic Analytics
Jean-Pierre Hubaux, Sylvain Chatel, Apostolos Pyrgelis, Christian Louis Knabenhans
Homomorphic encryption, which enables the execution of arithmetic operations directly on ciphertexts, is a promising solution for protecting privacy of cloud-delegated computations on sensitive data. However, the correctness of the computation result is no ...
2022On Succinct Non-interactive Arguments in Relativized Worlds
Succinct non-interactive arguments of knowledge (SNARKs) are cryptographic proofs with strong efficiency properties. Applications of SNARKs often involve proving computations that include the SNARK verifier, a technique called recursive composition. Unfort ...
SPRINGER INTERNATIONAL PUBLISHING AG2022Efficient protocols for oblivious linear function evaluation from ring-LWE
An oblivious linear function evaluation protocol, or OLE, is a two-party protocol for the function f (x) = ax + b, where a sender inputs the field elements a, b, and a receiver inputs x and learns f (x). OLE can be used to build secret-shared multiplicatio ...
IOS PRESS2022Protecting privacy through metadata analysis
Although encryption hides the content of communications from third parties, metadata, i.e., the information attached to the content (such as the size or timing of communication) can be a rich source of details and context. In this dissertation, we demonstr ...
EPFL2022