Ubuntu Security Notice USN-769-1 – Tavis Ormandy discovered that libwmf incorrectly used memory after it had been freed when using its embedded GD library. If a user or automated system were tricked into opening a crafted WMF file, an attacker could cause a denial of service or execute arbitrary code with privileges of the user invoking the program.
You can download this advisory from the following link: https://packetstormsecurity.com/files/download/77256/USN-769-1.txt
Source: https://packetstormsecurity.com/files/77256/Ubuntu-Security-Notice-769-1.html