GnuPG: OpenPGP protocol attack

Background

GnuPG is complete and free replacement for PGP, a tool for secure communication and data storage.

Description

A flaw has been identified in an integrity checking mechanism of the OpenPGP protocol.

Impact

An automated system using GnuPG that allows an attacker to repeatedly discover the outcome of an integrity check (perhaps by observing the time required to return a response, or via overly verbose error messages) could theoretically reveal a small portion of plaintext.

Workaround

There is no known workaround at this time.

Resolution

All GnuPG users should upgrade to the latest version:

 # emerge --sync
 # emerge --ask --oneshot --verbose ">=app-crypt/gnupg-1.4.1"