Dr.ing. F.W. Hahn | People Pages: Find employees & contact details

I am a member of the Semantics, Cyber Security and Services group at the University of Twente in the Netherlands.

Before joining the University of Twente, I was a permanent researcher at SAP Security Research in Karlsruhe, Germany. There I worked in the area applied cryptography, in particular on searchable encryption and encrypted databases. I obtained my Ph.D. with distinction from the Karlsruhe Institute of Technology (KIT) in Germany.

My interests are widespread in topics that are related to security and privacy, and my research is particularly focused on data encryption during processing for data outsourcing scenarios. These research results have various real-world applications such as encrypted storage for cloud computing, privacy-preserving machine-learning and protection of biometric data.

Expertise

Computer Science
- Attack
- Biometric Template Protection
- Homomorphic Encryption
- Keyword Search
- Privacy Preserving
- Symmetric Encryption
- Protection Scheme
- Fully Homomorphic Encryption

Organisations

Publications

2025

Fully Homomorphic Encryption for Privacy-Preserving Collaborative Machine Learning (2025)[Thesis › PhD Thesis - Research UT, graduation UT]. University of Twente. Mazzone, F.https://doi.org/10.3990/1.9789036568067Practical Biometric Search under Encryption: Meeting the NIST Runtime Requirement without Loss of Accuracy (2025)IEEE Transactions on Biometrics, Behavior, and Identity Science, 7(4), 710-727. Bassit, A., Hahn, F., Veldhuis, R. & Peter, A.https://doi.org/10.1109/TBIOM.2025.3545751Efficient Ranking, Order Statistics, and Sorting under CKKS (2025)In SEC '25: Proceedings of the 34th USENIX Conference on Security Symposium (pp. 8541-8558). Article 438. USENIX Association. Mazzone, F., Everts, M. H., Hahn, F. & Peter, A.https://doi.org/10.5555/3766078.3766516How to Securely Shuffle?: A survey about Secure Shufflers for privacy-preserving computations (2025)[Working paper › Preprint]. ArXiv.org. Damie, M., Hahn, F., Peter, A. & Ramon, J.https://doi.org/10.48550/arXiv.2507.01487Revisiting the Attacker’s Knowledge in Inference Attacks Against Searchable Symmetric Encryption (2025)In Applied Cryptography and Network Security - 23rd International Conference, ACNS 2025, Proceedings (pp. 370-399) (Lecture Notes in Computer Science; Vol. 15826 LNCS). Springer. Damie, M., Leger, J. B., Hahn, F. & Peter, A.https://doi.org/10.1007/978-3-031-95764-2_15Template recovery attack on encrypted face recognition systems with unprotected decision using synthetic faces (2025)Frontiers in Imaging, 4. Article 1476377. Bassit, A., Hahn, F., Rezgui, Z., Otroshi Shahreza, H., Veldhuis, R. & Peter, A.https://doi.org/10.3389/fimag.2025.1476377Revisiting the attacker's knowledge in inference attacks against Searchable Symmetric Encryption (2025)[Working paper › Preprint]. Damie, M., Leger, J.-B., Hahn, F. & Peter, A.https://doi.org/10.48550/arXiv.2504.09879Privacy-Preserving Vertical K-Means Clustering (2025)[Working paper › Preprint]. ArXiv.org. Mazzone, F., Brown, T., Kerschbaum, F., Wilson, K. H., Everts, M., Hahn, F. & Peter, A.https://doi.org/10.48550/arXiv.2504.07578Evaluating Membership Inference Attacks in heterogeneous-data setups (2025)[Working paper › Preprint]. ArXiv.org. van Dartel, B., Damie, M. & Hahn, F.https://doi.org/10.48550/arXiv.2502.18986Encrypt What Matters: Selective Model Encryption for More Efficient Secure Federated Learning (2025)In Data and Applications Security and Privacy XXXIX: 39th IFIP WG 11.3 Annual Conference on Data and Applications Security and Privacy, DBSec 2025, Gjøvik, Norway, June 23-24, 2025, Proceedings (pp. 96-115) (Lecture Notes in Computer Science; Vol. 15722). Springer. Mazzone, F., Badawi, A. A., Polyakov, Y., Everts, M., Hahn, F. & Peter, A.https://doi.org/10.1007/978-3-031-96590-6_6

Research profiles

Affiliated study programs

Courses academic year 2025/2026

Courses in the current academic year are added at the moment they are finalised in the Osiris system. Therefore it is possible that the list is not yet complete for the whole academic year.

Courses academic year 2024/2025

Address

University of Twente

Zilverling (building no. 11), room 2025
Hallenweg 19
7522 NH Enschede
Netherlands

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