Ubuntu Security Notice USN-335-1 – Yan Rong Ge discovered that heartbeat did not sufficiently verify some packet input data, which could lead to an out-of-boundary memory access. A remote attacker could exploit this to crash the daemon (Denial of Service).
You can download this advisory from the following link: https://packetstormsecurity.com/files/download/49339/USN-335-1.txt
Source: https://packetstormsecurity.com/files/49339/Ubuntu-Security-Notice-335-1.html