Secunia Security Advisory – Ubuntu has issued an update for krb5. This fixes some vulnerabilities, which can be exploited by malicious people to cause a DoS (Denial of Service).
You can download this advisory from the following link: https://packetstormsecurity.com/files/download/87620/sa39023.txt
Source: https://packetstormsecurity.com/files/87620/Secunia-Security-Advisory-39023.html