Welcome to provsec@CISPA!
We are a research group at the CISPA Helmholtz Center for Information Security in Saarbrücken, where we work on the foundations of modern cryptography through the lens of provable security. We analyze cryptographic schemes used in practice to obtain strong and concrete security guarantees, and we design new cryptographic schemes and protocols motivated by real-world applications. This often involves developing new formal models, security notions, and proof techniques.
Our research spans a broad range of topics in applied and theoretical cryptography. In particular, we work on authenticated key exchange and secure messaging, public-key encryption and signature schemes with advanced functionalities, post-quantum cryptography, anonymous and privacy-preserving cryptographic protocols, and the theory of tight security.
News
Three papers accepted at CRYPTO 2026 🎉 — check out our new results on updatable KEMs, anamorphic encryption and Just-in-Time-OPRFs (to appear soon). Thanks to all co-authors!
Together with Martijn Stam, Doreen organizes ProTeCS, a workshop on Proofs and Proof Techniques for Cryptographic Security, as an affiliated event at EUROCRYPT 2026 in Rome. We are very happy to have Bart Mennink and Mike Rosulek as invited speakers!
Doreen and Sabrina Kunzweiler launch PELICAN 🐦, an Équipe Associée funded by Inria to improve the provable security of isogeny-based cryptographic protocols. The funding supports mutual visits between our groups.
Xiangyu joins the PKC 2027 program committee. 📋
Leveled Isogeny Problems with Hints accepted at PKC 2026 🎉 Great work Subham!
Two papers accepted at EUROCRYPT 2026 🔐 — Secure Cloud Storage and The Algebraic Isogeny Model. See you in Rome!
Team
Visitors
Camryn Steckel — Aug 2026
Marvin Beckmann — Jul 2026
Marc Houben, Sabrina Kunzweiler — Jun 2026
Hans Heum — Nov 2025
Paul Rösler, Lea Thiemt — Mar 2025
Jonas Janneck, Jonas Meers — Feb 2025
Alumni
Weidan Ji — Remote Intern, Jun–Dec 2025
Agni Datta — Intern, Jun–Aug 2025
Publications
Teaching
Theoretical Foundations of Applied Cryptography
Cryptographic Foundations of Secure Messaging
Provable Security of Key Exchange Protocols