gnupg -- OpenPGP protocol attack

A vulnerability in OpenPGP can be used by attackers to recover partial plaintexts from messages employing symmetric encryption. Researchers Serge Mister and Robert Zuccherato of Entrust have developed a chosen-ciphertext attack method that can be used against OpenPGP messages encrypted using cipher feedback (CFB) mode. The attack takes advantage of an integrity check feature that is intended to save time by aborting futile and possibly lengthy decryption attempts.

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