Black Hat Apple has fixed a flaw in Safari that exposed user names, email addresses, and other sensitive information when the browser visited booby-trapped websites.
The update, which included an unrelated fix for a separate information disclosure vulnerability in Safari, comes a day before security researcher Jeremiah Grossman is scheduled to show attendees of the Black Hat Security conference in Las Vegas how to trick the AutoFill feature in the Apple browser into turning over detailed user information with no user input except visiting a particular website. Grossman said previously he had brought it to Apple's attention privately but received no response from the company.
In a bulletin published Tuesday, Apple said it had squashed the bug by prohibiting AutoFill from using user information without user action. Grossman, who is scheduled to speak about the vulnerability on Wednesday, said he hasn't had a chance to test the patch to see if it completely fixes the bug.
The vulnerability allowed webmasters to add simple code to their sites that siphoned highly personal information stored in a user's Mac or Windows address book. By default, the user's full name, email address, location, employer, and other information were free for the taking, and all that was required is that the information already be entered in the "My Card" record of address books included in OS X, Windows, or Outlook address books.
Apple's prompt action is testament to the power of full disclosure, which argues users are best protected when detailed information about vulnerabilities are widely disclosed. Many companies argue details should be shared only privately with the software maker until a patch is issued. Apple didn't publicly acknowledge the flaw until mainstream publications such as The New York Times and The Wall Street Journal published articles about the flaw, calling into question of the wisdom of so-called responsible disclosure.
Separately, Apple fixed a separate Safari bug that allowed webmasters to download system files using a specially designed RSS feed. The fix was credited to Billy Rios, a security researcher who recently left Microsoft for Google. Apple also patched more than a dozen bugs in Webkit. ®