WebKit in Apple Safari before 5.0.1 on Mac OS X 10.5 through 10.6 and Windows, and before 4.1.1 on Mac OS X 10.4; and webkitgtk before 1.2.6; does not properly handle just-in-time (JIT) compiled JavaScript stubs, which allows remote attackers to execute arbitrary code or cause a denial of service (application crash) via a crafted HTML document, related to a "reentrancy issue."
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A11777
http://www.vupen.com/english/advisories/2011/0552
http://www.vupen.com/english/advisories/2011/0216
http://www.vupen.com/english/advisories/2011/0212
http://www.vupen.com/english/advisories/2010/2722
http://www.ubuntu.com/usn/USN-1006-1
http://www.securityfocus.com/bid/42020
http://www.redhat.com/support/errata/RHSA-2011-0177.html
http://www.mandriva.com/security/advisories?name=MDVSA-2011:039
http://support.apple.com/kb/HT4276
http://secunia.com/advisories/43086
http://secunia.com/advisories/43068
http://secunia.com/advisories/41856
http://lists.opensuse.org/opensuse-security-announce/2011-01/msg00006.html
http://lists.opensuse.org/opensuse-security-announce/2010-10/msg00000.html
http://lists.apple.com/archives/security-announce/2010//Jul/msg00001.html