gpg in GnuPG before 1.4.2.2 does not properly verify non-detached signatures, which allows attackers to inject unsigned data via a data packet that is not associated with a control packet, which causes the check for concatenated signatures to report that the signature is valid, a different vulnerability than CVE-2006-0455.

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".

GnuPG (GPG) 1.0.2, and other versions up to 1.2.3, creates ElGamal type 20 (sign+encrypt) keys using the same key component for encryption as for signing, which allows attackers to determine the private key from a signature.