The windows functionality in WebKit in Apple Safari before 5.0.4 allows remote attackers to bypass the Same Origin Policy, and force the upload of arbitrary local files from a client computer, via a crafted web site.
http://www.securitytracker.com/id?1025183
http://www.securityfocus.com/bid/46816
http://support.apple.com/kb/HT4566
http://lists.apple.com/archives/security-announce/2011//Mar/msg00004.html