The Apache HTTP Server in Apple Mac OS X before 10.6.2 enables the HTTP TRACE method, which allows remote attackers to conduct cross-site scripting (XSS) attacks via unspecified web client software.
http://lists.apple.com/archives/security-announce/2009/Nov/msg00000.html
http://support.apple.com/kb/HT3937
http://www.mandriva.com/security/advisories?name=MDVSA-2009:300