Decoding supercodes of Gabidulin codes and applications to cryptanalysis

Abstract

This article discusses the decoding of Gabidulin codes and shows how to extend the usual decoder to any supercode of a Gabidulin code at the cost of a significant decrease of the decoding radius. Using this decoder, we provide polynomial time attacks on the rank-metric encryption schemes RAMESSES and LIGA.

arXiv commentPQCrypto 2021. The Sage code is available on Github: https://github.com/mbombar/Attack_on_LIGA