Whether it be in Bond movies or in the real world, spies are fitted with the latest and most innovative eavesdropping techniques and devices. From smart lasers, microchips, pen cameras, and of course hacking your phone, these devices allow conversations to be heard from afar. However, now researchers from Ben-Gurion University, claim they have found a way to bug a room without any government-issued super expensive gear, but rather using equipment that can be bought online and paired with an algorithm, they can turn any hanging light bulb into a bug, recording your private conversation.

With a clear line of sight to a standard LED light bulb, your next private conversation may have a few more ears listening

This innovative sound hack called “Lamphone” examines the eavesdropping of conversations from hundreds of feet away, by analyzing the sound vibrations that bounce off the glass of the hanging light bulb. Using a laptop, telescope, and an electro-optical sensor, which can all be purchased for under a grand, the research team pitched out on a bridge overlooking the university, about 80 feet away from their target office which had a standard E27 LED light bulb hanging from the ceiling.  

The researchers’ three telescopes fitted with electro-optical sensors were able to successfully document even the smallest changes in light coming from vibrations absorbed by the light bulb, which are caused by sound waves coming from inside the room. Next, the vibrations were transformed into raw data, then processed through proprietary software and compressed into a sound file. The researchers were able to successfully identify the music of Coldplay and the Beatles playing in the room, as well as perfectly recognizing a Donald Trump speech.

The recovered sound files are extremely accurate, so much so that the researchers claim that the conversations were easily transcribed by Google’s TTS (text-to-speech) API, and music on the other hand, was immediately identified by apps like Shazam and SoundHound.  

The research team explains that unlike laser-based microphones which can be detected by optic sensors, their light bulb method is practically undetectable. Add to the fact, that the would-be listeners never have to physically enter the targeted room and can be listening from a hundred feet away, unlike other sound-based spying devices. Although, before we get too excited, the researchers did note that the sounds in the targeted room were played at a higher volume than standard conversation. However, they also added that they were using relatively basic equipment, noting that with more high-tech gear they could spy from even farther away, and detect even softer sounds coming out of the room.  

Ben Nassi, Yaron Pirotin, and Boris Zadov make up the team heading the research and will present their findings at the Black Hat conference in August.