Security researchers will demonstrate how a web page can be armed to take control of network routers at today's RSA security conference.
Researcher Dan Kaminsky will show how browser flaws can be used to get hackers past corporate firewalls by compromising the Internet's Domain Name System (DNS).
At the root of web security is the same origin policy - where web pages run within a sandbox and are prevented from infecting other web pages. This allows most network equipment to communicate with each other only if they come from the same host name.
"But one name can be mapped via DNS to many IP addresses, some local and others not. The effect? You come to my webpage, and I can establish a VPN onto your LAN. And that's only the beginning," said Kaminsky.
The attack, called a DNS rebinding attack, would work on devices connected to a network, such as printers, that use a default password and a web-based admin interface, said Kaminsky, director of penetration testing with IOActive.