Ubuntu Security Notice 855-1 – Mark Martinec discovered that HTML::Parser incorrectly handled strings with incomplete entities. An attacker could send specially crafted input to applications that use HTML::Parser and cause a denial of service.
You can download this advisory from the following link: https://packetstormsecurity.com/files/download/82513/USN-855-1.txt
Source: https://packetstormsecurity.com/files/82513/Ubuntu-Security-Notice-855-1.html