Two-factor authentication and ‘trusted’ devices

“I challenged hackers to investigate me and what they found out is chilling” is an interesting article – it’s the story of a couple who challenged a hacking team to pen-test their digital lives. To give some context to the following quote, their laptop has been compromised and user ID and password for their on-line banking account at Chase has been stolen by the ethical hacking team:

Chase.com uses a two-step verification system, which momentarily stymied SpiderLabs’ hackers. Every time she or I logs on from an IP address that Chase doesn’t recognize, it offers to send us an activation code via text to our mobile phones. But a search of Charlotte’s hard drive revealed Chase cookies, which the team copied and used to convince Chase that she was logging in from home.

You could argue that if your PC has been this thoroughly compromised then you have bigger problems, but it still points out how limited some two-factor authentication systems can be if you allow devices to be remembered/trusted.