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://github.com/audreyt/module-signature/commit/8a9164596fa5952d4fbcde5aa1c7d1c7bc85372f
http://ubuntu.com/usn/usn-2607-1