The Form Autofill feature in Apple Safari before 6.0.1 does not restrict the filled fields to the set of fields contained in an Autofill popover, which allows remote attackers to obtain the Me card from an Address Book via a crafted web site.
https://exchange.xforce.ibmcloud.com/vulnerabilities/78681
http://www.securityfocus.com/bid/55625
http://support.apple.com/kb/HT5502
http://lists.apple.com/archives/security-announce/2012/Sep/msg00005.html