An Efficient Attack on a Code-Based Signature Scheme

Baldi et al. have introduced in [BBC+ 13] a very novel code based signature scheme. However we will prove here that some of the bits of the signatures are correlated in this scheme and this allows an attack that recovers enough of the underlying secret structure to forge new signatures. This cryptanalysis was performed on the parameters which were devised for 80 bits of security and broke them with 100, 000 signatures originating from the same secret key.