A bug in Microsoft's Internet Explorer (IE) browser gives phishers a way to scan the hard drives of Google Desktop users, according to an Israeli hacker. Because of a flaw in the way IE processes Web pages, a malicious Web site could use the attack to steal sensitive information like credit card numbers or passwords from the hard drives of its visitors.
"Google Desktop users who use IE are currently completely exposed," wrote hacker Matan Gillon in an e-mail interview. "An experienced attacker can covertly harvest their hard drives for sensitive information such as passwords and credit card numbers. Since Google also indexes e-mails which can be read in the Web interface itself, it's also possible to access them using this attack."
Gillon has posted an extensive description of how such an attack would work, along with a proof of concept exploit, on his blog at http://www.hacker.co.il/security/ie/css_import.html.
The IE bug concerns the way Microsoft's browser processes Web page layout information using the CSS (Cascading Style Sheets) format. The CSS format is widely used to give Web sites a consistent look and feel, but attackers can take advantage of the way that IE processes CSS to get Google Desktop to reveal sensitive information.
Hackers would first need to trick users into visiting a malicious Web site for the attack to be successful, Gillon said. The attack works with IE 6 and Google Desktop v2, but it may also work on other versions of Microsoft's browser, but it does not work with non-Microsoft browsers like Firefox or Opera, he said.
Users need to be particularly wary of the Web sites they visit these days, because of a second unpatched IE vulnerability that could be used to take over a user's PC. Hackers posted sample code that exploited this problem over a week ago and Microsoft said that hackers are already using the code in attacks. As with the CSS problem, users must first be tricked into visiting a malicious Web site for this second IE bug to be exploited.
Microsoft executives were unavailable to comment on the CSS bug, but a spokeswoman for the company's public relations agency said the issue is being investigated. Microsoft is not aware of any attacks resulting from the hole, she said.