Your Headphones Can Hear You
It’s common knowledge that your webcam can spy on you, but did you know that your headphones can too? Here is how.
Published: Monday, November 28th 2016
After a picture circulated showing Facebook CEO, Mark Zuckerberg covering the webcam on his laptop, people started taping over their webcams again. This, in fear that it could be hacked and that someone could spy on them without them knowing.
It has been proven that your webcam can indeed be hacked. Furthermore, the little light showing that it's on can actually be turned off. It turns out, however, that your webcam isn't the only thing that can be used to spy on you.
Proof That Your Earphones Are Spying On You
Researchers at Ben-Gurion University of the Negev have demonstrated malware that can turn computers into perpetual eavesdropping devices, even without a microphone.
This malware - which is actual working code - is known as SPEAKE(a)R.
"The fact that headphones, earphones, and speakers are physically built like microphones, and that an audio port's role in the PC can be reprogrammed from output to input, creates a vulnerability that can be abused by hackers," says Prof. Yuval Elovici, director of the BGU Cyber Security Research Center (CSRC) and member of BGU's Department of Information Systems Engineering.
"This is the reason people, like Facebook Chairman and Chief Executive Officer, Mark Zuckerberg, tape up their mic and webcam," says Mordechai Guri, lead researcher and head of Research and Development at the CSRC. "You might tape the mic, but it would be unlikely to tape the headphones or speakers."
SPEAKE(a)R shows off how a determined hacker can repurpose the tech inside the speakers in your computer to turn it into voice-recording devices, without you knowing. What makes it even scarier, is that this works even when the speakers on your computer have been disabled or, even, completely removed.
The speakers in your headphones turn electromagnetic signals into sound through a membrane's vibrations. This membrane can be reverse-engineered to record sound instead of just playing it.
Realtek's Audio Chips
There is also a little known feature in Realtek's audio chips (which are used in a number of computers). This lets the audio jack do double duty by allowing it to record audio as well as transmit it.
The team from Ben-Gurion tested a pair of ordinary Sennheiser earbuds. These worked so well as a microphone that they were able to record clear audio of a man’s voice. This even though the man was standing just over six meters away from the computer.
The scariest part about all of this is that there is no easy fix. This is because it's not a software issue but, instead, a hardware issue with RealTek's chips.