Fergie's Tech Blog

Black Hat: Web Browser Attack Skirts Corporate Firewalls - UPDATE

Robert McMillan writes on CIO.com:

A 10-year-old security problem has come back to haunt corporate IT, a security researcher told an audience at the Black Hat conference in Las Vegas Wednesday.

Dan Kaminsky, director of penetration testing for IO Active, showed how problems in the way browser software works with the Internet's domain name system could be exploited to give attackers access to any resources behind the corporate firewall.

He described a multi-step attack that could be used to scan corporate networks for data or vulnerabilities. But at the heart of the attack is a 1996 paper by Princeton researchers showing how a Java applet could be used to access systems on a victim's network. "It's one of the few things that's actually come back from the dead," Kaminsky said.

The fundamental problem, according to Kaminsky, is in the way that Web browser software decides how to trust other computers. This decision is based on the Internet domain name of the computer, and that DNS information can be misused, Kaminsky said. "It's a binding problem," he said during an interview after his talk. "They assume a value is not changing, but the attacker can change it whenever he chooses."

More here.

UPDATE: 7 August 2007 11:00 PDT: Lisa Vaas has really nice write-up of the mecahnics of this here on eWeek.

posted by Fergie @ 8/02/2007 11:05:00 AM