San Francisco: A giant vulnerability in the Internet’s design is allowing criminals to silently redirect traffic to Web sites under their control. The problem is being fixed, but its extent remains unknown and many people are still at risk.
The gaping security hole enables a scam that targets ordinary people typing in a legitimate Web address. It happens because hackers are now able to manipulate the machines that help computers find Web sites. If the trick is done properly, computer users are unlikely to detect whether they’ve landed at a legitimate site or an evil double maintained by someone bent on fraud.
High risk of virus attacks and identity-fraud scams
The bug’s existence was revealed nearly a month ago. Since then, criminals have pulled off at least one successful attack, directing some AT&T Inc. Internet customers in Texas to a fake Google site. The phony page was accompanied by three programs that automatically clicked on ads, with the profits for those clicks flowing back to the hackers.
The AT&T attack probably would have stayed quiet had it not affected the Internet service of Austin, Texas-based BreakingPoint Systems Inc., which makes machines for testing networking equipment and has Moore as its labs director. He disclosed the incident in hopes it would help uncover more breaches.
How does it happen?
The underlying flaw is in the Domain Name System (DNS), a network of millions of servers that translate words typed into Web browsers into numerical codes that computers can understand.
Getting from one place to another on the Internet typically requires a trip through several DNS servers, including some that accept incoming data and store parts of it. That opens them up for potential attack.
What this means is that a computer user in say, San Francisco, might type www.yahoo.com and head straight to the real Yahoo site, while at the same moment, a user in New York _ whose traffic is routed through different DNS servers might type that same Web address and end up on a phony duplicate site.
How did it get discovered?
The researcher who discovered it, Dan Kaminsky of Seattle-based computer security consultant IOActive Inc., announced 8 July that he’d found a major weakness in DNS. But he kept the rest secret because he wanted to give companies that run vulnerable servers a month to apply patches software tweaks that cover the security hole. He coordinated with Microsoft Corp., Cisco Systems Inc., Sun Microsystems Inc. and other major vendors to simultaneously issue patches.
He got two weeks before bad guys and good guys alike accurately guessed the basics of what Kaminsky discovered.
How widespread will the attacks be?
Just how widespread the attacks have been is hard to tell. The evidence of tampering can disappear before an Internet provider even learns there’s a problem.
The patching of DNS servers has accelerated. Kaminsky said 84% of the servers he tested at the beginning of the process were vulnerable. That has dropped to around 31%.
More details about the vulnerability are expected to emerge Wednesday, when Kaminsky speaks at the Black Hat computer security conference in Las Vegas. The conference and its sister event, DefCon, draw researchers, government investigators and corporate executives eager to learn about new vulnerabilities and how to protect against them.
DNS attacks aren’t new. But Kaminsky discovered a way to link together some widely known weaknesses in the system, so that an attack that would have taken hours or days can now take only seconds. Meanwhile, from the point of view of Internet criminals looking for easier access to other people’s money and secrets clearly goes up.”