Secunia Security Advisory – Ubuntu has issued an update for ntp. This fixes some vulnerabilities, which can be exploited by malicious people to cause a DoS (Denial of Service) or compromise a vulnerable system.
You can download this advisory from the following link: https://packetstormsecurity.com/files/download/77674/sa35137.txt
Source: https://packetstormsecurity.com/files/77674/Secunia-Security-Advisory-35137.html