Microsoft probes possible IE 7 phishing hole

Microsoft is investigating a possible vulnerability in Internet Explorer 7 that could help cybercrooks launch phishing scams, the company said Wednesday.

An attacker can use an error message displayed by the latest Microsoft browser to send Web surfers to malicious Web sites that will display with the address of a trusted site, such as a bank, Aviv Raff, a developer in Israel, wrote on his Web site. Raff included an example where the error message directs the Web surfer to a site of his choice.

Microsoft is looking into the issue, a representative said. "Microsoft is not aware of any attacks attempting to use the reported vulnerability," the representative said in an e-mailed statement. "Microsoft will continue to investigate... to help provide additional guidance for customers as necessary."

The vulnerability relates to the message IE displays when Web page loading is aborted, Raff wrote. An attacker can rig the message by creating a malicious link. The message will offer a link to retry loading the page; hitting it brings up the attacker's page, but showing an arbitrary Web address, he wrote.

To launch a phishing attack, an attacker can create a Web link that purports to go to a trusted site, such as a bank. When clicked, the link results in a rigged error page. Following the reload link on that page will display the attacker's Web site with the address of the trusted site in the IE 7 address bar, Raff wrote.

Phishing attacks are a prevalent Internet threat that typically use fraudulent Web sites and spam e-mail to trick people into giving up personal information such as Social Security numbers and credit card details.

IE 7 on Windows Vista and Windows XP are affected, Raff wrote.