By now you're probably well aware that hackers have the ability to hijack webcams like the one in your computer. With the right malware and a little luck, they can take control and snap pictures and record video and audio at will. It's a frightening scenario that scores of victims have dealt with in recent years.
Protecting yourself against a peeping tom who wants to peer through your webcam is simple enough. Just slap a piece of electrical tape over it when it's not in use. The microphone isn't quite so easy to shield, however... and that could be a very serious problem.
You might think that the webcam is the bigger concern, but it turns out that a well-placed microphone is the key to an incredibly clever new hacking technique that sounds like it's straight out of science fiction. Researchers have figured out how to remotely spy on a computer screen by listening in with a microphone.
No, that doesn't make any sense. Screens are made for looking at things... so how, exactly, can someone listen to the electronic images they display?
It's due to a phenomenon called coil whine. Coil whine is typically a high-pitched sound that electronic components produce when they're forced to do a lot of hard work. Old tube-style televisions and monitors were notorious for coil whine, but today's high-tech LCD displays produce it, too.
A team of security researchers discovered that they could listen to coil whine with the help of a well-placed microphone. The raw data the team recorded doesn't look like anything to get worked up about:
These lines, as Ars Technica reports, merely represent the intensity of a particular pixel on the display. This is just the first stage of the attack, however. A specially-trained machine learning algorithm was able to translate the recordings. With the help of this specialized software tool, the team successfully identified websites that were being displayed with 96.5% accuracy.
It's not likely that hackers will be utilizing a technique like this any time soon. There are much simpler ways out there to snoop on someone's computer activities. Still, the potential is there... and as we continue to fill our homes with smart speakers, connected baby monitors and security cameras equipped with microphones this kind of attack will become all the more appealing to cyber criminals.
