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, and SeaMonkey before 2.13.2 allow remote attackers to bypass the Same Origin Policy and read the Location object via a prototype property-injection attack that defeats certain protection mechanisms for this object.

The nsLocation::CheckURL function in 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, and SeaMonkey before 2.13.2 does not properly determine the calling document and principal in its return value, which makes it easier for remote attackers to conduct cross-site scripting (XSS) attacks via a crafted web site, and makes it easier for remote attackers to execute arbitrary JavaScript code by leveraging certain add-on behavior.

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, and SeaMonkey before 2.13.2 do not prevent use of the valueOf method to shadow the location object (aka window.location), which makes it easier for remote attackers to conduct cross-site scripting (XSS) attacks via vectors involving a plugin.

Mozilla Firefox before 16.0.1, Firefox ESR 10.x before 10.0.9, Thunderbird before 16.0.1, Thunderbird ESR 10.x before 10.0.9, and SeaMonkey before 2.13.1 omit a security check in the defaultValue function during the unwrapping of security wrappers, which allows remote attackers to bypass the Same Origin Policy and read the properties of a Location object, or execute arbitrary JavaScript code, via a crafted web site.

The Inter-process Communication (IPC) implementation in Google Chrome before 18.0.1025.168, as used in Mozilla Firefox before 38.0 and other products, does not properly validate messages, which has unspecified impact and attack vectors.