Jana Sotáková, PhD student at QuSoft and UvA, won the best-paper award at the IACR flagship conference CRYPTO 2020 for her article “Breaking the Decisional Diffie-Hellman Problem for Class Group Actions Using Genus Theory”.
Jana works on post-quantum cryptography, which is the field designing and evaluating protocols that would replace the encryption that we use nowadays with ones that are safe against adversaries with quantum computers. She specializes in proposals based on isogenies of elliptic curves, which connects well to her background in number theory. “I am happy to see the beautiful abstract theory used in practical attacks”, says Jana.
With her co-authors Jana was able to identify and attack a weakness in a variant of a widely-studied proposal. “Before our work, it was not believed that such an exploit could be possible, yet we constructed an attack that is extremely practical in some cases. We also have a good understanding of which variants do not admit such an attack. So, as a research community, we can focus on studying the unbroken variants”.
Jana is a second year PhD student and started her research at QuSoft and UvA in 2019. Her supervisors are Christian Schaffner (ILLC, UVA), Serge Fehr (CWI) and Peter Bruin (MI Leiden). And the winning article is co-authored with Dr. Wouter Castryck and Dr. Frederik Vercauteren of the Computer Security and Industrial Cryptography (COSIC) research group in the Department of Electrical Engineering at KU Leuven.