Safari AutoFill can be exploited by malicious web sites
A flaw in the implementation of Safari’s AutoFill mechanism can be exploited to grab Mac users’ names, street addresses, and e-mail addresses. Apparently, the web browser will give away a user’s Mac OS X Address Book data if asked by a malicious web site.
http://www.macsimumnews.com/index.php/archive/safari_autofill_can_be_exploited_by_malicious_web_sites/