Secunia Security Advisory – Ubuntu has issued an update for squid. This fixes two vulnerabilities, which potentially 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/40028/sa16807.txt
Source: https://packetstormsecurity.com/files/40028/Secunia-Security-Advisory-16807.html

