Crypto Reading Group - Mojtaba Fadavi and Anna Henderson-HQC PKE/KEM

This session is devoted to the HQC cryptosystem itself, in both its public-key encryption and key-encapsulation forms. We will explain how the scheme works, describe its main components and design choices, and discuss the corresponding security analysis, including comments on the post-quantum setting. By this stage, the reading group should have enough background to appreciate both the structure and the rationale of HQC.

References: [1] and [4]

[1] C. Aguilar-Melchor, O. Blazy, J.-C. Deneuville, P. Gaborit and G. Zémor. Efficient Encryption From Random Quasi-Cyclic Codes. In IEEE Transactions on Information Theory, vol. 64, no. 5, pp. 3927–3943, 2018.

[4] HQC Team. Hamming Quasi-Cyclic (HQC), NIST Submission, 2025.