Use-after-free vulnerability in Apple Safari 4.x before 4.1.2 and 5.x before 5.0.2 allows remote attackers to execute arbitrary code or cause a denial of service (application crash) via run-in styling in an element, related to object pointers.
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A11729
http://www.vupen.com/english/advisories/2010/3046
http://www.securityfocus.com/bid/43049
http://support.apple.com/kb/HT4456
http://support.apple.com/kb/HT4333
http://secunia.com/advisories/42314
http://lists.apple.com/archives/security-announce/2010//Sep/msg00001.html
http://lists.apple.com/archives/security-announce/2010//Nov/msg00003.html