We prove that the path-finding problem in isogeny graphs and the endomorphism ring
problem for supersingular elliptic curves are equivalent under reductions of polynomial …

Generating a supersingular elliptic curve such that nobody knows its endomorphism ring is a
notoriously hard task, despite several isogeny-based protocols relying on such an object. A …

We present SCALLOP-HD, a novel group action that builds upon the recent SCALLOP
group action introduced by De Feo, Fouotsa, Kutas, Leroux, Merz, Panny and Wesolowski in …

We introduce a new primitive named Delay Encryption, and give an efficient instantiation
based on isogenies of supersingular curves and pairings. Delay Encryption is related to …

We optimise the verification of the SQIsign signature scheme. By using field extensions in
the signing procedure, we are able to significantly increase the amount of available rational …

We study two important families of problems in isogeny-based cryptography and how they
relate to each other: computing the endomorphism ring of supersingular elliptic curves, and …

For primes p ≡ 3\bmod 4, we show that setting up CSIDH on the surface, ie, using
supersingular elliptic curves with endomorphism ring Z (1+-p)/2, amounts to just a few sign …

We initiate the study of threshold schemes based on the Hard Homogeneous Spaces (HHS)
framework of Couveignes. Quantum-resistant HHS based on supersingular isogeny graphs …

Given two elliptic curves and the degree of an isogeny between them, finding the isogeny is
believed to be a difficult problem—upon which rests the security of nearly any isogeny …

An important open problem in supersingular isogeny-based cryptography is to produce,
without a trusted authority, concrete examples of 'hard supersingular curves' that is …