The host is installed with Mozilla Firefox before 16.0.2, Firefox ESR 10.x before 10.0.10, Thunderbird before 16.0.2, Thunderbird ESR 10.x before 10.0.10 or SeaMonkey before 2.13.2 and is prone to cross-site scripting (XSS) vulnerabilities. The flaws are present in the applications, which fail to prevent use of the valueOf method to shadow the location object (aka window.location). Successful exploitation allows remote attackers to conduct cross-site scripting (XSS) attacks via vectors involving a plugin.