Ubuntu Security Notice 1011-3 - USN-1011-1 fixed a vulnerability in Firefox. This update provides the corresponding update for Xulrunner. Morten Krakvik discovered a heap-based buffer overflow in Firefox. If a user were tricked into navigating to a malicious site, an attacker could cause a denial of service or possibly execute arbitrary code as the user invoking the program.
ea538fb7a396cad06d7b022df27a6427f3c3f3de5e776aa2b925db67faeff274