About me

I am an assistant professor in the Computer Science department of the Université Libre de Bruxelles.

From Oct. 2024 to Fev. 2026, I was a post-doctoral researcher at UCLouvain in the Crypto Group.

Before that, I was a PhD student at UVSQ in the CRYPTO team under the supervision of Christina Boura, Henri Gilbert (ANSSI), and Yann Rotella.

My main interest is in symmetric cryptanalysis. I have worked on the analysis of both primitives and modes. Regarding primitive cryptanalysis, I particularly enjoy looking at differential cryptanalysis and algebraic attacks. As for mode cryptanalysis, I enjoy pretty much anything related to generic attacks.

Publications

Here is my dblp. Below is a list of my most recent publications.

Christina Boura, Patrick Derbez, Baptiste Germon, Rachelle Heim Boissier, María Naya-Plasencia. SPEEDY: Caught at last. ASIACRYPT 2025. eprint version

Xavier Bonnetain, Rachelle Heim Boissier, Gaëtan Leurent, André Schrottenloher. Improving Generic Attacks Using Exceptional Functions. CRYPTO 2024. eprint version

Christina Boura, Nicolas David, Patrick Derbez, Rachelle Heim Boissier, María Naya-Plasencia. A generic algorithm for efficient key recovery in differential attacks – and its associated tool. EUROCRYPT 2024. eprint version

Henri Gilbert, Rachelle Heim Boissier, Jérémy Jean, Jean-René Reinhard. Cryptanalysis of Elisabeth-4. ASIACRYPT 2023. eprint version

Henri Gilbert, Rachelle Heim Boissier, Louiza Khati, Yann Rotella. Generic Attack on Duplex-Based AEAD Modes Using Random Function Statistics. EUROCRYPT 2023. eprint version

Christina Boura, Nicolas David, Rachelle Heim Boissier, María Naya-Plasencia. Better Steady than Speedy: Full Break of SPEEDY-7-192. EUROCRYPT 2023. eprint version

Christina Boura, Rachelle Heim Boissier, Yann Rotella. Breaking Panther. AFRICACRYPT 2022. eprint version

Rachelle Heim Boissier, Yann Rotella. Algebraic Collision Attacks on Keccak. Transactions on Symmetric Cryptology 2021. ToSC version here

Teaching

• Algo 1 for first-year Computer Science students (Spring)
• Cryptography for first-year Computer Science master's students (Fall)

I have previously given tutorials at Université de Versailles Saint-Quentin-en-Yvelines.

• Bases et codage de l'informatique (IN202) for first-year Computer Science students (Spring)
• Introduction to (Python) programming (IN100) for first-year Computer Science students (Fall)

• Cryptography for third-year students (Spring)
• Cryptography for first-year master's students (Fall)

• Mathematics for computer science (IN310) for second-year students (Fall)
• Cryptography for first-year master students (Fall)

Awards

Prix de Thèse of the GDR Sécurité informatique: webpage of the prize

Talks

Conferences

Eurocrypt 2024. A generic algorithm for efficient key recovery in differential attacks – and its associated tool. May 29th 2024. slides

Asiacrypt 2023. Cryptanalysis of Elisabeth-4. December 5th 2023. slides

Journées C2 2023. Cryptanalysis of Elisabeth-4. October 16th 2023. slides

Eurocrypt 2023. Generic Attack on Duplex-Based AEAD Modes Using Random Function Statistics. April 26th 2023. slides

Africacrypt 2022. Breaking Panther. July 18th 2022. slides

Journées C2 2022. Attaque structurelle par échange contre des versions réduites d'AES-128. April 14th 2022. slides

FSE 2022. Algebraic Collision Attacks on Keccak. March 22nd 2022. slides, video

Seminars

Boolean Modeling and Analysis of Learning With Rounding . Slides (latest version)

Slides jointly created with Jules Baudrin.

Dagstuhl Seminar 260161 (Talk was given by Jules Baudrin). February 3rd 2026.

Séminaire C2. January 16th 2026.

Generic attacks based on functional graphs . Slides (latest version)

Séminaire Algo de Caen. November 18th 2025.

ULB Computer Science seminar (Université de Caen Normandie). March 6th 2025.

CYS Group seminar (King's College London). June 3rd 2024.

ALMASTY seminar (Lip6, Sorbonne Université). May 3rd 2024.

Rennes Crypto Seminar. September 22nd 2023.

The key recovery step in differential attacks. . Slides (latest version)

Inria, Paris. December 5th 2024.

Outreach

Les fonctions de hachage (in French) . Slides (latest version)

Finale du concours Alkindi, Paris. June 22nd 2023.

Contact