Ubuntu Update for Linux kernel vulnerabilities USN-1143-1
Please Install the Updated Packages.
It was discovered that the message header parser in Dovecot did not properly handle '\0' characters in header names. This could allow a remote attacker to cause a denial of service through a crafted email message by crashing the Dovecot daemon or corrupting mailboxes.
dovecot on Ubuntu 11.04 , Ubuntu 10.10 , Ubuntu 10.04 LTS