The integrity check feature in OpenPGP, when handling a message that was encrypted using cipher feedback (CFB) mode, allows remote attackers to recover part of the plaintext via a chosen-ciphertext attack when the first 2 bytes of a message block are known, and an oracle or other mechanism is available to determine whether an integrity check failed.

References

• https://nvd.nist.gov/vuln/detail/CVE-2005-0366
• http://eprint.iacr.org/2005/033
• http://eprint.iacr.org/2005/033.pdf
• http://securitytracker.com/id?1013166
• http://www.gentoo.org/security/en/glsa/glsa-200503-29.xml
• http://www.kb.cert.org/vuls/id/303094
• http://www.mandriva.com/security/advisories?name=MDKSA-2005:057
• http://www.novell.com/linux/security/advisories/2005_07_sr.html
• http://www.osvdb.org/13775
• http://www.pgp.com/library/ctocorner/openpgp.html
• http://www.securityfocus.com/bid/12529