gpgv in GnuPG before 1.4.2.1, when using unattended signature verification, returns a 0 exit code in certain cases even when the detached signature file does…

gpgv in GnuPG before 1.4.2.1, when using unattended signature verification, returns a 0 exit code in certain cases even when the detached signature file does not carry a signature, which could cause programs that use gpgv to assume that the signature verification has succeeded. Note: this also occurs when running the equivalent command "gpg --verify".