News & Events
Here we are giving you a peek into what keeps us busy, motivated and happy day in and day out.
Kenny Paterson gives an invited talk at ArcticCrypt 2025.
Kenny was invited to give a talk at ArcticCrypt 2025, held in Longyearbyen, Svalbard this week. Svalbard is located inside the Arctic circle and enjoys 125 days of continuous daylight during the summer. Kenny’s talk with title “Living in a Parallel Universe: the Quantum Internet and Quantum Key Distribution” was delivered in a “midnight” session at the conference starting at 12:15am on Tuesday 8th July. Kenny was able to keep his audience awake with a talk exploring the promise of, and challenges faced in achieving the vision of, the Quantum Internet.
10.07.2025
Welcome Martin!
Martin Hirt joins the Applied Crypto group as a Senior Scientist on 1 August 2025.
Martin did his Master's and PhD at ETH. His current research areas are multi-party computation, Byzantine agreement, and efficiency of secure protocols. Martin was awarded the VSETH Golden Owl in 2017 and the TCC test of time award in 2020. We are looking forward to welcoming Martin to the group, where his expertise in foundational aspects of cryptography and his extensive teaching experience will be highly valued.
07.07.2025
Best Paper Award at CODASPY 2025
Congratulations to Mia Filić and Kenny Paterson for winning a best paper award at CODASPY 2025 for their paper entitled “Probabilistic Data Structures in the Wild: A Security Analysis of Redis”. The paper resulted from a collaboration with Jonas Hofmann (formerly a Master’s student with the Applied Cryptography group, now a doctoral student at TU Darmstadt), Sam Markelon (PhD student at the University of Florida, and previously a visitor to the group thanks to a ThinkSwiss Research scholarship), and Dr. Anupama Unnikrishnan (formerly a postdoc with the group, now Executive Director of the ETH Quantum Center). The paper provides a detailed security analysis of Probabilistic Data Structures (PDS) supported in the Redis in-memory database system in adversarial settings, presenting a total of 10 attacks against the PDS in Redis, as well as proposing countermeasures to the attacks.
Read the full version of the paper here: external page https://eprint.iacr.org/2024/1312.
01.07.2025
Applied Crypto at Crypto '25 Santa Barbara
The paper "Hybrid Obfuscated Key Exchange and KEMs", by Felix Günther, Michael Rosenberg, Douglas Stebila and Shannon Veitch, was accepted at Crypto.
The work presents an OKEM combiner that achieves hybrid IND-CCA security with hybrid ciphertext obfuscation guarantees, leading to the development of Drivel, a modified pq-obfs protocol compatible with hybrid OKEMs. This enables practical implementations, such as combining obfuscated versions of DHKEM and ML-KEM, and provides the first hybrid PAKE protocol secure against adaptive corruptions in the UC model.
20.06.2025
CAW 2025 Recordings Now Online
Recordings of our CAW sessions are now online (thank you Miro!). If you missed our workshop and are curious about the talks, you can find them external page here!
18.06.2025
Applied Crypto Course FS25 - Lab Prizes
This year's edition of the Applied Cryptography course has come to an end!
As part of the course, we run a Capture-the-Flag style competition, were students have to find and exploit cryptographic vulnerabilities in toy servers we create for this purpose.
This year's race was fierce -- here are the three students who solved all of the challenges the fastest! The prize - custom trophies and Applied Crypto mugs!
AC '25 was brought to you by: Felix and Florian, Shannon and Lenka, Yuanming, Kien and Matteo!
30.05.2025
Cryptography in a Changing World: Navigating Geopolitical Uncertainty and Security Risks - Eurocrypt Community Event
Martin Albrecht and Kenny Paterson are the organizers of a community event at this year's Eurocrypt in Madrid.
The event aims to set up a discusson on what we as a community can and should do in light of a dramatically changing domestic and international political landscape. It will take place on Wednesday, May 7, 14:30-16:00 (Room Callao, 3rd floor).
05.05.2025
IACR Distinguished Lecture: Kenny Paterson
The IACR Distinguished Lecture is an annual honour recognizing researchers who have made important contributions to cryptology.
Kenny Paterson has been awarded this year's Distinguished Lecture, and will be presenting at Eurocrypt in Madrid, on Tuesday, May 6, at 14:30. You can follow it in person or online if you are registered to the conference.
04.05.2025
Cryptographic Applications Workshop at Eurocrypt 25
The second edition of the Cryptographic Applications Workshop will be hosted as an associated event at this year's Eurocrypt in Madrid, on Sunday.
CAW focuses on the construction and analysis of cryptography built for practice. Inspired by the Real World Crypto Symposium, it aims to provide a forum for cryptographers in academia and industry to exchange ideas and insights, bridging the gap between research and real-world applications.
CAW is brought to you by Matilda Backendal, Miro Haller, Laura Hetz and Matteo Scarlata.
03.05.2025
Peer2PIR: Private Queries for IPFS at S&P 2025
The InterPlanetary File System (IPFS) is a peer-to-peer network for storing data in a distributed file system, hosting over 190,000 peers spanning 152 countries. Despite its prominence, IPFS has very limited privacy guarantees, leaking every query in the network to the peers. In a recent work, Miti Mazmudar, Shannon Veitch and Rasoul Akhavan Mahdavi try to fix that, integrating state-of-art PIR protocols in the context of distributed systems. "Peer2PIR: Private Queries for IPFS" will be presented this May at S&P in San Francisco.
24.04.2025
AC Group at YRCS
The Applied Crypto Group took part in this spring's edition of the Young Researcher Crypto Seminar, hosted by University of Konstanz.
Our group members presented:
- "Probabilistic Data Structures in Adversarial Settings" - Mia Filic
- "D(e)rive with Care: Lessons Learned from Analyzing Real-World Multi-Input Key Derivation Functions" - Sebastian Clermont (TU Darmstadt) and Matteo Scarlata
- "Two-Server Authenticated Private Information Retrieval with Client-Preprocessing" - Laura Hetz
05.03.2025
Rune visits the Applied Crypto Group
Rune Fielder is in the fifth year of his PhD at TU Darmstadt, under the supervision of Prof. Marc Fischlin.
Rune visited the AC group last week, and presented his work on "BUFFing signatures, post-quantum Signal, and deniable authentication with malicious verifiers”.
We have a record of successful collaborations with Marc and his group, and we enjoyed learning more about Rune's research!
03.03.2025
Applied Crypto at Eurocrypt 2025 - Madrid
Some of our work will appear at Eurocrypt this spring!
- "On the Soundness of Algebraic Attacks against Code-based Assumptions" by Simon-Philipp Merz, Miguel Cueto Noval, Patrick Stählin, Akin Ünal.
- "Key Derivation Functions Without a Grain of Salt" by Matilda Backendal, Sebastian Clermont, Marc Fischlin and Felix Günther.
- "Analysis of the Telegram Key Exchange" by Martin R. Albrecht, Lenka Mareková, Kenny Paterson, Eyal Ronen, Igors Stepanovs.
Looking forward to the talks!
03.02.2025
Applied Crypto at RWC 2025 - Sofia
The Applied Cryptography Group will have a strong presence at this year's RWC, with 5 talks from our group accepted to the programme!
- "Breaking and Fixing Length Leakage in Content-Defined Chunking", by Kien Tuong Truong, Matteo Scarlata, Simon-Philipp Merz, Felix Günther and Kenny Paterson.
- "D(e)rive with Care: Lessons Learned from Analyzing Real-World Multi-Input Key Derivation Functions", by Matilda Backendal, Sebastian Clermont, Marc Fischlin, Felix Günther, Miro Haller and Matteo Scarlata.
- "Mind the Gap! Secure File Sharing, from Theory to Practice", by Matilda Backendal, David Balbás, Nicola Dardanis, Miro Haller and Matteo Scarlata.
- “Kemeleon: Elligator-like Obfuscation for Post-Quantum Cryptography”, by Felix Günther, Michael Rosenberg, Douglas Stebila and Shannon Veitch.
- "Provable Security for End-to-End Encrypted Cloud Storage", by Matilda Backendal, Hannah Davis, Felix Günther, Miro Haller, Kenny Paterson.
We look forward to sharing our research with the wider cryptographic community, and to network with all the awesome people attending RWC! See you in Sofia!
27.01.2025
Applied Crypto at Usenix Security 25
Francesca Falzon will be presenting her work with Tianxin Tang, a former postdoc in our group, titled "Learning from Functionality Outputs: Private Join and Compute (PJC) in the Real World" at this year's Usenix Security Symposium in August 2025.
PJC, a two-party protocol proposed by Google, is used for applications like ad conversion and generalizes their private set intersection sum protocol. It enables two parties with key-value databases to privately compute the inner product of values with intersecting keys. Although the output of this functionality is not usually included in the security model of multi-party computation (MPC), it could pose privacy risks in real-world applications.
Francesca and Tianxin's work examines these risks, focusing on an adversary within the protocol who could exploit four practical attacks to compromise the other party's input privacy. The study underscores the importance of considering functionality output in the MPC security model to mitigate these threats.
20.01.2025
