YARR, as used in Mozilla Firefox before 7.0, Thunderbird before 7.0, and SeaMonkey before 2.4, allows remote attackers to cause a denial of service (application crash) or possibly execute arbitrary code via crafted JavaScript.
lists.apple.com/archives/Security-announce/2011//Oct/msg00000.html
lists.apple.com/archives/Security-announce/2011//Oct/msg00001.html
lists.apple.com/archives/Security-announce/2011//Oct/msg00002.html
lists.apple.com/archives/Security-announce/2011//Oct/msg00004.html
lists.opensuse.org/opensuse-updates/2011-10/msg00002.html
secunia.com/advisories/46315
secunia.com/advisories/49055
support.apple.com/kb/HT4981
support.apple.com/kb/HT4999
support.apple.com/kb/HT5000
support.apple.com/kb/HT5001
www.mandriva.com/security/advisories?name=MDVSA-2011:141
www.mandriva.com/security/advisories?name=MDVSA-2011:142
www.mozilla.org/security/announce/2011/mfsa2011-42.html
bugs.webkit.org/show_bug.cgi?id=61585
bugzilla.mozilla.org/show_bug.cgi?id=653672
oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A14408