The New Tab page in Mozilla Firefox before 17.0 uses a privileged context for execution of JavaScript code by bookmarklets, which allows user-assisted remote attackers to run arbitrary programs by leveraging a javascript: URL in a bookmark.
lists.opensuse.org/opensuse-security-announce/2012-11/msg00021.html
lists.opensuse.org/opensuse-security-announce/2013-01/msg00022.html
lists.opensuse.org/opensuse-updates/2012-11/msg00090.html
lists.opensuse.org/opensuse-updates/2012-11/msg00093.html
secunia.com/advisories/51369
secunia.com/advisories/51434
secunia.com/advisories/51439
www.mozilla.org/security/announce/2012/mfsa2012-95.html
www.securityfocus.com/bid/56623
www.ubuntu.com/usn/USN-1638-1
www.ubuntu.com/usn/USN-1638-2
www.ubuntu.com/usn/USN-1638-3
bugzilla.mozilla.org/show_bug.cgi?id=765628
oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A16503