Secunia Security Advisory – Debian has issued an update for libtheora. This fixes some vulnerabilities, which can be exploited by malicious people to cause a DoS (Denial of Service) and potentially compromise an application using the library.
You can download this advisory from the following link: https://packetstormsecurity.com/files/download/89458/sa39735.txt
Source: https://packetstormsecurity.com/files/89458/Secunia-Security-Advisory-39735.html