A security researcher has crafted a gadget that looks like a USB wall charger, but is actually a keylogger that targets Microsoft wireless keyboards.

Researcher Samy Kamkar produced the device, dubbed KeySweeper, that secretly monitors any of the wireless keyboards within range and has the ability to sniff, decrypt, log and report all keystrokes, according to VentureBeat.

While the spy tool does function as a USB charger, it has an internal rechargeable battery, allowing it to continue to work after it's unplugged. Another feature included is a web-based tool included in the device that allows for live keystroke monitoring, as well as the ability to send SMS alerts when specific keywords are entered.

Details on building the device – which Kamkar said is possible for as little as $10 – were released on GitHub.

Microsoft is reportedly investigating the device.