Mozilla Firefox before 2.0.0.15, Thunderbird 2.0.0.14 and earlier, and SeaMonkey before 1.1.10 allow remote attackers to execute arbitrary code via an XUL document that includes a script from a chrome: URI that points to a fastload file, related to this file's "privilege level."
Weaknesses in this category are related to the management of permissions, privileges, and other security features that are used to perform access control.