Alex Pellegrini

I am a mathematician. I got my Ph.D. in Mathematics from Eindhoven University of Technology, the Netherlands, where I worked under the guidance of Tanja Lange and Alberto Ravagnani. I am a member of the Coding Theory and Cryptology group within the Department of Mathematics and Computer Science.

Before joining TU/e, I spent a year in the Cryptology and Data Security group at the University of Bern, Switzerland, focusing on quorum systems.

I earned my M.Sc. in Mathematics in 2019 from the University of Trento, specializing in coding theory and cryptography. My master's thesis was titled "On two algebraic decision problems and their instances."

I also hold a Bachelor's degree in Computer Science, obtained in 2015 from the University of Trento. My bachelor's thesis, "Supporting joins and numerical computations over encrypted databases," explored homomorphic encryption techniques for outsourced data processing.

List of Publications and Preprints

1. Caminata A., Cartor R., Meneghetti A., Mora R., Pellegrini A.: Quadratic Modelings of Syndrome Decoding. PQCrypto25.       (https://ia.cr/2024/1975)

2. Pellegrini A., Vorstermans M.: Analysis of REDOG: The Pad Thai Attack. PQCrypto25. (https://ia.cr/2024/1967)

3. Chee S., Jeong K.C., Lange T., Lee N., Pellegrini A., Ryu H.: Analysis of Layered ROLLO-I: A BII-LRPC code-based KEM. Communications in Cryptology, Volume 1 - Issue 3. (https://eprint.iacr.org/2024/230).

4. Pellegrini, A., Tognolini, G.: Breaking HWQCS: a code-based signature scheme from high weight QC-LDPC codes. CBCrypto25. (https://eprint.iacr.org/2024/117).

5. Cottaar J, Hövelmanns K., Hülsing A., Lange T., Mahzoun M., Pellegrini A., Ravagnani A, Schäge S., Trimoska M., de Weger B.: Report on evaluation of KpqC candidates (https://eprint.iacr.org/2023/1853).

6. Lange T., Pellegrini A., Ravagnani A.: On the security of REDOG. ICISC 2023. Lecture Notes in Computer Science (https://eprint.iacr.org/2023/1205).

7. Meneghetti A., Pellegrini A., Sala M.: On the equivalence of two post-quantum cryptographic families. Annali di Matematica Pura ed Applicata (1923 -) (2022) (https://arxiv.org/abs/2109.05806).

8. Pellegrini A., Zanolini L.: An Algebraic Model for Quorum Systems (https://arxiv.org/abs/2005.08536).

9. Di Nicola A., Vettori B., Angheben M., Pellegrini A., Margeory Sanchez Quispe Y., D’Amore L., Nicolar R., Palomo Martinez J., Camelia Iorgulescu G., Mihai Chiriac V.: Payback. Towards a EU Data Management System for Seized Assets. (.pdf)(website).

 Theses

1. Attacking and Enhancing Code-Based Cryptography. Ph.D. Thesis (slides).

2. On two algebraic decision problems and their instances. Master's Thesis.

3. Supporting Joins and Numerical Computations over Encrypted Databases. Bachelor's Thesis (slides).

Other Publications

These are informal publications that are posted somewhere on the web, some of which have later made it into a paper.

1. Pellegrini A. Vorstermans M. : Analysis of REDOG: the Pad Thai attack (.pdf)

2. Pellegrini A. : Breaking 2/3 of Layered-ROLLO-I-2023-10-20  (.pdf)

3. Pellegrini A. : An efficient message recovery attack on the new Modified-Layered-ROLLO-I (.pdf)

4. Lange T., Pellegrini A. : Analysis of Layered-ROLLO-I. Kpqc bulletin board (.pdf)

 Talks

• 10.7.2025. Breaking Layered ROLLO-I. ArcticCrypt 2025. Longyearbyen, Svalbard, Norway. Slides.

• 17.6.2025. Quadratic modelings of syndrome decoding. ACCESS. Slides.

• 9.4.2025. Quadratic modelings of syndrome decoding. PQCrypto 2025. Taipei, Taiwan. Slides.

• 28.11.2024. Streamlining higher-genus McEliece. Young Cryptographers in Genova. Genova, Italy. Slides.

• 11.9.2024. The Pad Thai attack. Kpqc TU/e - Seminar. Eindhoven, The Netherlands. Slides.

• 26.5.2024. Complexity of solving syndrome decoding problems as a system of quadratic equations. CBCrypto 2024. Zurich, Switzerland. Slides.

• 1.3.2024. Linear algebra attacks on code based schemes - Breaking Layered-ROLLO-I and HWQCS. Crypto Working Group seminars. Utrecht, The Netherlands. Slides.

• 6.1.2024. Breaking Layered ROLLO-I. JMM 2024 - AMS Special Session on Cryptography and Related Fields. San Francisco, California. Slides.

• 30.11.2023. On the security of REDOG. ICISC 2023. Seoul, South Korea. Slides.

• 11.10.2023. REDOG. Kpqc-Seminar. Eindhoven, The Netherlands. Slides.

• 10.10.2023. Enhanced pqsigRM. Kpqc-Seminar. Eindhoven, The Netherlands. Slides.

• 04.10.2023. Layered-ROLLO-I. Kpqc-Seminar. Eindhoven, The Netherlands. Slides.

• 13.07.2023. On the security of REDOG. Kpqc - Seminar. Eindhoven, The Netherlands. (Slides, Video)

• 18.04.2023. On Enhanced-pqsigRM. Kpqc TU/e - Seminar. Eindhoven, The Netherlands. Slides

• 17.02.2023. Code-based cryptography and AG codes. COGNAC -Conference On alGebraic varieties over fiNite fields and Algebraic geometry Codes. Marseille, France. Slides

• 24.11.2022. Code-based cryptography and AG codes. DIAMANT Symposium Autumn 2022. Leiden, The Netherlands.  Slides

Code

Here are links to software supporting some of the papers listed above. This software is not at all optimized, but proves that attacks actually attack and that the considered schemes can be broken in little time on a laptop.

• Signature forgery attack on HWQCS and related code. Github repo.

• Message recovery attack on levels 128 and 192 of Layered-ROLLO-I-2023-10-20. Sage code.

• Message recovery attack on Layered-ROLLO-I. Sage code.

• Reduction attack on Modified-Layered-ROLLO-I. Sage code.

• Message recovery attack on REDOG. Sage code.

Teaching Assistance

• Introduction to Cryptology, Fall semester (2020-2021-2022-2023)

• Algebra and Discrete Mathematics, Winter semester (2020-2021-2022-2023)

• Applied Cryptography, Winter semester (2020-2021-2022-2023)