Ubuntu Security Notice USN-737-1 – It was discovered that the Base64 encoding functions in libsoup did not properly handle large strings. If a user were tricked into connecting to a malicious server, an attacker could possibly execute arbitrary code with user privileges.
You can download this advisory from the following link: https://packetstormsecurity.com/files/download/75768/USN-737-1.txt
Source: https://packetstormsecurity.com/files/75768/Ubuntu-Security-Notice-737-1.html