Table of contents

  • This session has been presented October 17, 2025 (13:45 - 14:45).

Description

  • Speaker

    Shibam Ghosh - Inria

The partial-sums technique introduced by Ferguson et al. (2000) achieved a 6‑round AES attack with time complexity 2^{52} S‑box evaluations, a benchmark that has stood since. In 2014, Todo and Aoki proposed a comparable approach based on the Fast Fourier Transform (FFT). 

In this talk, I will show how to combine partial sums with FFT to get "the best of both worlds". The resulting attack on 6‑round AES has a complexity of about 2^{46.4} additions, and I will outline how to implement it efficiently. A proof-of-concept implementation achieves a speedup of more than 32x over the previous best result, setting a new practical record for 6‑round AES after nearly 25 years.

Practical infos

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