Safari 5.0.1 and 4.1.1 Address AutoFill Security Flaw

Impact: Safari's AutoFill feature may disclose information to websites without user interaction

Description: Safari's AutoFill feature can automatically fill out web forms using designated information in your Mac OS X Address Book, Outlook, or Windows Address Book. By design, user action is required for AutoFill to operate within a web form. An implementation issue exists that allows a maliciously crafted website to trigger AutoFill without user interaction. This can result in the disclosure of information contained within the user's Address Book Card. To trigger the issue, the following two situations are required. First, in Safari Preferences, under AutoFill, the "Autofill web forms using info from my Address Book card" checkbox must be selected. Second, the user's Address Book must have a Card designated as "My Card". Only the information in that specific card is accessed via AutoFill. This issue is addressed by prohibiting AutoFill from using information without user action. Devices running iOS are not affected. Credit to Jeremiah Grossman of WhiteHat Security for reporting this issue.

Grossman reported the issue to Apple on June 17th, but went public with his disclosure last week in order to alert customers after failing to receive significant response from Apple. After Grossman's public disclosure, Apple acknowledged the issue and promised that it was working on a fix.