The PGP signature parsing in Module::Signature before 0.74 allows remote attackers to cause the unsigned portion of a SIGNATURE file to be treated as the signed portion via unspecified vectors.
https://metacpan.org/changes/distribution/Module-Signature
https://github.com/audreyt/module-signature/commit/8a9164596fa5952d4fbcde5aa1c7d1c7bc85372f
http://www.openwall.com/lists/oss-security/2015/04/23/17