Sabine Oechsner
I am an Assistant Professor at the Vrije Universiteit Amsterdam in the Theoretical Computer Science group. I'm also affiliated with the VUSec group.
My research interests are cryptography and provable security, as well as their intersection with formal methods and programming languages. I am particularly interested in making the worlds meet in a way that furthers our understanding of provable security: Instead of merely reproducing existing cryptographic proofs with tool support, my goal is to use formal verification as an opportunity to understand how to write better proofs with high assurance, both on paper and in a machine-checkable way.
News
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The Zama Cryptanalysis Grant Program is going to fund our project on the real-world security of MPC protocols. Peter Scholl and I are planning to hire some interns for this project for summer 2026. More information to follow.
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I am honored to give a keynote at CSF 2025.
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I'm on the PC of PLAS 2025!
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"Rushing at SPDZ: On the Practical Security of Malicious MPC Implementations" was accepted to S&P 2025. Joint work with Alexander Kyster, Frederik Huss Nielsen, and Peter Scholl.
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In March 2024, I joined the Vrije Universiteit Amsterdam as Assistant Professor in the Theoretical Computer Science group.
Research
Publications
- Rushing at SPDZ: On the Practical Security of Malicious MPC Implementations
with Alexander Kyster, Frederik Huss Nielsen, and Peter Scholl
S&P 2025
[eprint] [video]
- Adaptive Distributional Security for Garbling Schemes with O(|x|) Online Complexity
with Estuardo Alpirez Bock, Chris Brzuska, Pihla Karanko, and Kirthivaasan Puniamurthy
Asiacrypt 2023
[eprint]
- A State-Separating Proof for Yao’s Garbling Scheme
with Chris Brzuska
CSF 2023
[eprint]
- CRAFT: Composable Randomness Beacons and Output-Independent Abort MPC From Time
with Carsten Baum, Bernardo David, Rafael Dowsley, Ravi Kishore, and Jesper Buus Nielsen
PKC 2023
[eprint]
- Bringing State-Separating Proofs to EasyCrypt - A Security Proof for Cryptobox
with François Dupressoir and Konrad Kohbrok
CSF 2022
[eprint] [slides]
- Formal security analysis of MPC-in-the-head zero-knowledge protocols
with Nikolaj Sidorenco and Bas Spitters
CSF 2021
[eprint] [video]
- TARDIS: A Foundation of Time-Lock Puzzles in UC
with Carsten Baum, Bernardo David, Rafael Dowsley, and Jesper Buus Nielsen
Eurocrypt 2021
[eprint] [video]
- Adaptive Security of Practical Garbling Schemes
with Zahra Jafargholi
Indocrypt 2020
[eprint] [video]
- Towards Practical Lattice-Based One-Time Linkable Ring Signatures
with Carsten Baum and Huang Lin
ICICS 2018
[eprint]
- More Efficient Commitments from Structured Lattice Assumptions
with Carsten Baum, Ivan Damgård, Vadim Lyubashevsky, and Chris Peikert
SCN 2018
[eprint]
- Computer-Aided Proofs for Multiparty Computation with Active Security
with Helene Haagh, Aleksandr Karbyshev, Bas Spitters, and Pierre-Yves Strub
CSF 2018
[eprint]
- Compact Zero-Knowledge Proofs of Small Hamming Weight
with Ivan Damgård, Ji Luo, Peter Scholl, and Mark Simkin
PKC 2018
[eprint] [slides]
Activities
Editorial Board
Program Committee
Organization and co-chairing
- 2025: Workshop on Proofs and Proof Techniques for Cryptographic Security (ProTeCS), Eurocrypt 2025 affiliated event, Location: Madrid, Spain
- 2025: Workshop on Computer-Aided Proofs of Security (CAPS), Eurocrypt 2025 affiliated event, Location: Madrid, Spain
- 2024: Workshop on Proofs and Proof Techniques for Cryptographic Security (ProTeCS), Eurocrypt 2024 affiliated event, Location: Zurich, Switzerland
- 2022-2024: Edinburgh Crypto Seminar, the weekly cryptography seminar at the University of Edinburgh
- 2021: WRePP: Workshop on Reduction Proofs in Pseudocode, co-organized with Chris Brzuska, co-located with CRYPTO 2021, Location: Santa Barbara, USA/virtual
- 2020: WoDUP: Workshop on developing, using and teaching cryptographic proofs, co-organized with Chris Brzuska and Markulf Kohlweiss, co-located with EUROCRYPT 2020, Location: Zagreb, Croatia/cancelled due to pandemic
- 2019-2020: Aarhus Crypto Seminar, the weekly seminar of the Cryptography group at Aarhus University. Here is the list of talks during that time.
- 2019: Aarhus Crypto Day 2019
I received my PhD from Aarhus University in 2019 for my research on "Constructions and Proof Techniques for Secure Computation". My PhD was supervised by Ivan Damgård. During that time I also visited NTT Secure Platform Laboratories as well as IDC Herzliya (now Reichman University), working with Elette Boyle. I then stayed in Aarhus for a postdoc with Jesper Buus Nielsen before continuing my research in the Security and Privacy group at the University of Edinburgh.
While my PhD started out more traditionally by constructing cryptography, I am now leaning more towards the "proof techniques" side of provable security. Having been raised into cryptography at Aarhus University, I am particularly interested in cryptographic protocols and their security.
s.a.oechsner (at) vu.nl
How to pronounce my last name
The combination OE is an old spelling of the German letter Ö. The pronounciation is similar to the Scandinavian Ø or the French Œ, or the vowel in the English word learn. If you are in doubt, use O instead.
The CHS in the middle of my name is pronounced like X or KS in English.
How to spell my last name
The way it is spelled on all my publications: Oechsner.
But isn't OE actually Ö?
Yes and no. In most German words, Ö is indeed used instead of OE. But names are not ordinary words, and they certainly don't care about modern spelling rules. There is even a German brewery with that spelling. (We are not related though.)