firefox is vulnerable to arbitrary code execution. Several flaws were found in the processing of malformed web content. A web page containing malicious content could cause Firefox to crash or, potentially, execute arbitrary code with the privileges of the user running Firefox.
lists.opensuse.org/opensuse-updates/2011-10/msg00002.html
secunia.com/advisories/46315
www.debian.org/security/2011/dsa-2312
www.debian.org/security/2011/dsa-2313
www.debian.org/security/2011/dsa-2317
www.mandriva.com/security/advisories?name=MDVSA-2011:139
www.mandriva.com/security/advisories?name=MDVSA-2011:140
www.mandriva.com/security/advisories?name=MDVSA-2011:141
www.mandriva.com/security/advisories?name=MDVSA-2011:142
www.mozilla.org/security/announce/2011/mfsa2011-36.html
www.mozilla.org/security/known-vulnerabilities/firefox36.html#firefox3.6.23
www.redhat.com/support/errata/RHSA-2011-1341.html
access.redhat.com/errata/RHSA-2011:1341
access.redhat.com/security/updates/classification/#critical
bugzilla.mozilla.org/show_bug.cgi?id=655098
bugzilla.mozilla.org/show_bug.cgi?id=660453
bugzilla.mozilla.org/show_bug.cgi?id=662215
bugzilla.mozilla.org/show_bug.cgi?id=665360
oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A13957