The Mozilla Maintenance Service in Mozilla Firefox before 22.0 on Windows does not properly handle inability to launch the Mozilla Updater executable file, which allows local users to gain privileges via vectors involving placement of a Trojan horse executable file at an arbitrary location.
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A17126
https://bugzilla.mozilla.org/show_bug.cgi?id=867056
http://www.mozilla.org/security/announce/2013/mfsa2013-62.html