Secunia Security Advisory – Ubuntu has issued an update for dovecot. This fixes a security issue, which can be exploited by malicious users to bypass certain security restrictions.
You can download this advisory from the following link: https://packetstormsecurity.com/files/download/62664/sa28434.txt
Source: https://packetstormsecurity.com/files/62664/Secunia-Security-Advisory-28434.html