Weak Keys in the Faure-Loidreau Cryptosystem

Abstract

Some types of weak keys in the Faure-Loidreau (FL) cryptosystem are presented. We show that from such weak keys the private key can be reconstructed with a computational effort that is substantially lower than the security level. The proposed key-recovery attack is based on ideas of generalized minimum distance (GMD) decoding for rank-metric codes