Symantec warns of router compromise

Security company Symantec has warned of an attack involving the subversion of routers.

The security company said this was the first time it had seen such an attack "in the wild," although the concept had been discussed a year ago by Symantec researchers, according to a Symantec blog post.

In the attack, which targeted users of an undisclosed Mexican bank, the intended victims received a spam e-mail claiming they had received an e-card, directing them to gusanto.com, a Spanish-language e-card site. However, the e-mail also had embedded HTML image tags that contained an HTTP get-request to the router to change its Domain Name System settings, according to Symantec's U.K. manager of quality assurance, Thomas Parsons.

The HTTP get-request redirects traffic flowing over the router to a specific IP address when the user attempts to access six domain names that are banking-related. Symantec requested that ZDNet UK not publish the IP address.

The attack is made possible by a cross-site scripting vulnerability in routers made by broadband-equipment company 2Wire that was reported in August last year, according to Symantec. Parsons said this was "a simple hack" and advised small to medium-size businesses to change default security settings on routers and educate users about clicking on suspicious links.

Tom Espiner of ZDNet UK reported from London.

[alegr]

No surprise

GET request is used to change settings in a popular router design by certain company whose name starts with 'C' and ends with 't'. The sad thing is that the product managers were warned about that four years ago.
Any webpage can issue GET request to your router, with arbitrary arguments, that's it. Should have used POST.

[magick_samurai]

Need security, not POST

POST isn't secure enough either, tho it does provide a bit more than GET. If you viewed a site they could still post to the router with a form and javascript. The GET method simply allows the attack to be done without javascript, using an image tag or the like.

The basis of this attack, while using XSS, is really more of a CSRF attack (Cross site referrer forgery.)

The users who this affect are ones logged into the router without login out (most routers use .htaccess and don't support logging out without clearing private data.)
These authenticated users are used to send data and change settings. Simple referrer checking in the router's web-interface programming would eliminate most of these problems.