Beware the coffee shop hacker: New breed of cyber criminal spies on your laptop by listening to signals even when it's OFFLINE

• Georgia Institute of Technology researchers reveal new hacking method
• They say hackers can 'listen in' to signals emitted by laptops and phones
• This means, even when offline, they could find out what you are doing
• It is very hard to track because the spying is 'silent'
• However, they say developers can create software to patch up the vulnerability in devices

By JONATHAN O'CALLAGHAN FOR MAILONLINE

PUBLISHED: 11:54 GMT, 9 January 2015 | UPDATED: 12:41 GMT, 9 January 2015

When your computer performs a spell check, opens a program or even just types a letter, it emits a tiny, imperceptible signal.

At least, it was thought to be imperceptible - but researchers say a new breed of hackers could 'listen' to these signals and find out what your computer is doing.

And now they are trying to devise methods to keep your computer safe from hackers employing this discreet technique.

The researchers at the Georgia Institute of Technology are investigating where these information 'leaks' originate so they can help hardware and software designers develop strategies to plug them.

Studying emissions from multiple computers, they have found a way to measure the strength of the leaks - known technically as 'side-channel signals' - and prioritise security efforts.

Worryingly, the signals don't even require your computer to be online - simply being active is enough for a hacker to listen in to what you are up to.

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