Biography

Hello! I am Huanhuan Chen, a fourth-year Ph.D. student in Computer Science at Delft University of Technology. I am very fortunate to be advised by Prof. dr. ir. Inald Lagendijk and Dr. Kaitai Liang in the Cybersecurity group since July 2021. Before that, I earned my Master’s degree in Mathematics from Nankai University.

I work in the field of applied cryptography. I am particularly interested in lattice-based cryptographic primitives and protocols, such as updatable encryption, fully homomorphic encryption, searchable encryption, and secure multi-party computation. I am also interested in the application of those cryptographic tools in privacy-preserving machine learning.

Publications

• [SIGMETRICS’25] Rui Wang, Xingkai Wang, Huanhuan Chen, Jérémie Decouchant, Stjepan Picek, Nikolaos Laoutaris, Kaitai Liang: MUDGUARD: Taming Malicious Majorities in Federated Learning using Privacy-Preserving Byzantine-Robust Clustering. ACM SIGMETRICS 2025.
• [ESORICS’24] Tjard Jan Langhout, Huanhuan Chen, Kaitai Liang: File-Injection Attacks on Searchable Encryption, Based on Binomial Structures. European Symposium on Research in Computer Security 2024.
• [ESORICS’24] Björn Ho, Huanhuan Chen, Zeshun Shi, Kaitai Liang: Similar Data is Powerful: Enhancing Inference Attacks on SSE with Volume Leakages. European Symposium on Research in Computer Security 2024.
• [CSF’24] Manning Zhang, Zeshun Shi, Huanhuan Chen, Kaitai Liang: Inject Less, Recover More: Unlocking the Potential of Document Recovery in Injection Attacks Against SSE. Computer Security Foundations Symposium 2024.
• [ASIACRYPT’23] Huanhuan Chen, Yao Jiang Galteland, Kaitai Liang: CCA-1 secure updatable encryption with adaptive security. Advances in Cryptology – ASIACRYPT 2023.
• [ESORICS’22] Steven Lambregts, Huanhuan Chen, Jianting Ning, Kaitai Liang: VAL: Volume and Access Pattern Leakage-Abuse Attack with Leaked Documents. European Symposium on Research in Computer Security 2022.
• [ESORICS’22] Huanhuan Chen, Shihui Fu, Kaitai Liang: No-Directional and Backward-Leak Uni-Directional Updatable Encryption Are Equivalent. European Symposium on Research in Computer Security 2022.
• [CYSARM‘21] Kevin Tjiam, Rui Wang, Huanhuan Chen, Kaitai Liang: Your smart contracts are not secure: investigating arbitrageurs and oracle manipulators in Ethereum. Proceedings of the 3rd Workshop on Cyber-Security Arms Race 2021.

     Preprint

• Huanhuan Chen, Mauro Conti, Thanassis Giannetsos, Kaitai Liang: Amortized Bootstrapping for Arbitrary Function Evaluation, within A Polynomial Modulus.

Teaching Assistant and Mentoring

    TA

• CSE3230 Algebra and Cryptography, BSc (2022/23 Q3, 2023/24 Q3).
• IN4191 Security and Cryptography, MSc (2021/22 Q1).

    Co-supervising (TU Delft)

• Zero-Knowledge Proofs
  • Lesley Franschman(MSc 2024): The Vesper Protocol: Leveraging Zero-Knowledge Proofs and SGX Enclaves in Hyperledger Fabric Smart Contracts.
• Attacks on Searchable Encryption
  • Tjard Langhout (MSc 2024): File-Injection Attacks on Searchable Encryption, Based on Binomial Structures.
  • Björn Ho (MSc 2023): Searchable Symmetric Encryption Attacks.
  • Hakan Ilbas (MSc 2023), Attacks on Searchable Symmetric Encryption Systems: Revisiting Similardata and File Injection Attacks.
  • Jeroen Thomas (MSc 2022), SSE Is Not As Secure As It Looks.
  • Steven Lambregts (MSc 2022), Revisit Attacks on Searchable Symmetric Encryption.
• Post-Quantum Crytogrphy
  • Matei Cristea-Enache (BSc 2021): Investigation on post-quantum digital signature systems based on multivariate equations.
  • Alexandra Feldman (BSc 2021): Investigation on lattices- and code-based post-quantum signature cryptosystems.
  • Lola Dekhuijzen (BSc 2021): A Comparison of Post-Quantum Code-Based Cryptosytems.

Talks

• CCA-1 Secure Updatable Encryption with Adaptive Security, Monash SSC Seminar, Monash University, Australia, April 16, 2024 (online).

• Homomorphic Evaluation of Convolutional Neural Networks, University of Padua, Italy, October 25, 2023.

Summer School

• Summer school on Cryptography. Ruhr University Bochum, Germany, August 26-30, 2024.
• COSIC Course on Cryptography and Cyber Security. KU Leuven, Belgium, July 1-4, 2024.
• Summer School on real-world crypto and privacy 2024. Vodice, Croatia, June 3-7, 2024.
• Summer School in Post-Quantum Cryptography. Eötvös Loránd University, Budapest, Hungary, August 1 – 5, 2022.
• Foundations and Applications of Lattice-based Cryptography. ICMS, Bayes Centre, Edinburgh, Britain, July 25 - 28, 2022 (online).

Award

First Prize in the Olympiad in Mathematics and Programming among Universities in Heilongjiang Province of China and the Far Eastern Region of Russia, 2013.

Visiting

• University of Padua. Host: Prof. Mauro Conti, October - November 2023.