Sid Stamm, Zulfikar Ramzan, and Markus Jakobsson have identified a clever, and potentially devastating, attack against home/wireless routers.

How does the attack works?

1. Attacker creates a webpage with containing the malicious Javascript code.
2. Victim visits the page
3. The code makes a login attempts into the users home broadband router and then attempts to change its DNS server settings to point to an attacker-controlled DNS server
4. Once the user.s machine receives the updated DNS settings from the router (after the machine is rebooted) future DNS requests are made to and resolved by the attacker.s DNS server.
5. Now the attacker basically owns the victim.s web connection.

The main condition for the attack to be successful is that the attacker can guess the router password. This is surprisingly easy, since home routers come with a default password that is uniform and often never changed.

They.ve written proof of concept code that can successfully carry out the steps of the attack on Linksys, D-Link, and NETGEAR home routers. If users change their home broadband router passwords to something difficult to guess, they are safe from this attack.

Additional details can be found here. There.s also a paper on the attack.

Note that the attack does not require the user to download any malicious software; simply viewing a web page with the malicious JavaScript code is enough.