20 Dec 2013

The hacker’s latest weapon: a simple microphone


Computers work silently, right? Beavering away on your desk without so much as a whimper. Wrong.

Get close to your computer. Really close. Get your ear right next to it. You can hear it humming.

The sound comes from many different sources: for example, the disc on which the computer’s information is held spins at different speeds, the power supply will also give off its own frequency of hum, the fan whirrs as it cools down the circuit boards.

And now, it seems, your computer’s subtle noises can give vital info to hackers.

New research from Israeli security experts alleges that the sounds can be used to crack the codes behind some of the most secure software in the industry.

By putting a microphone next to the computer, the researchers claimed they could listen to it as it decodes a message, and gradually work out the code used to encrypt it.

The company whose codes they claimed to detect is RSA – one of the world’s largest encryption firms – and it’s noteworthy that one of the chaps behind the research is the S in RSA, Adi Shamir.

The almost imperceptible sounds our computers make is turning into an intriguing area of tech security.

A researcher in Canada recently claimed to have discovered a virus that spreads by using microphones and speakers in laptops – enabling it to jump the “air-gap” which has traditionally been the best defence against the spread of computer viruses.

It’s worth keeping an eye – and perhaps an ear – on this developing area of info security.

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