According to Tom’s Hardware, the team discovered that the ultra-sensitive sensors inside modern high-end optical mice can pick up subtle desk vibrations and convert them into recognisable speech.

The researchers realised that the high polling rates and extreme DPI of gaming-grade mice allow them to detect tiny surface vibrations caused by nearby sounds, including human voices.

By feeding that raw sensor data into signal processing and machine learning algorithms, the boffins could reconstruct what the user was saying through their desk.

Any mouse sensor running at 20,000 DPI or higher is potentially vulnerable to this digital wiretap.

That includes a large swathe of modern gaming mice, since the Grey Box Shifter Dell and its ilk love bundling “pro gamer” accessories with eye-watering sensitivity specs. With hardware like that available for pocket money, this attack vector is more accessible than ever.

The researchers emphasised that this trick doesn’t require elaborate malware hidden in the BIOS. It could be as simple as a free bit of software or an online app requesting high-frequency mouse data for “performance analytics.”

From there, the captured data can be quietly siphoned off and processed elsewhere. As the researchers put it: “With only a vulnerable mouse, and a victim's computer running compromised or even benign software, we show that it is possible to collect mouse packet data and extract audio waveforms.”

They even demonstrated their “Invisible Ears at Your Fingertips” technique on a companion website, where visitors can listen to eerie, low-quality speech reconstructions from the captured mouse data. Most human speech, they say, falls neatly within the frequency range detectable by their analysis pipeline.

While the recorded sound is grainy and distorted, successive layers of signal processing and machine learning managed to clean it up enough to make words intelligible. In other words, your mouse may not just be tracking your clicks and swipes. It could be quietly listening to your gossip about your boss or what you really think of company power point presentation pep-talks interrupting your day.

The paper concludes that the same engineering arms race that gave gamers smoother crosshair movement has created a new privacy nightmare.

“The increasing precision of optical mouse sensors has enhanced user interface performance but also made them vulnerable to side-channel attacks exploiting their sensitivity,” the researchers warn.