Those who know how audio equipment works will be aware that microphones and speakers work on the same principle. Which is why it is surprising that it took this long for security researchers to build a proof of concept that uses headphones as listening devices to spy on people.
Called Speake(a)r repurposes the RealTek audio codec chip found in almost all computers. All it technically does is switch the output port to an input port. Impressively, this results in audio quality similar to that of an unpowered microphone for picking up audio in a room.
Unfortunately, it’s not easy to fix the vulnerability. The RealTek chip doesn’t allow the hack to be prevented, which means that there really is nothing that can be done except to prevent any malware from getting into the system in the first place.
The researchers pointed out that this attack is a proof of concept, and hasn’t actually been found in the wild yet. Which is good news, and RealTek should be working on an eventual fix. On the other hand, hackers are probably looking into using this kind of attack now that they know it works.