The host is installed with Mozilla Firefox before 3.5.12 or 3.6.x before 3.6.9 or Thunderbird before 3.0.7 or 3.1.x before 3.1.3 or SeaMonkey before 2.0.7 and is prone to a denial of service vulnerability. A flaw is present in the applications, which fail to handle a specially crafted font in a data. Successful exploitation could allow attackers to cause a denial of service or memory corruption and application crash or possibly execute arbitrary code.