John Z Black

John Z Black May 4, 2026 Vulnerabilities & Patching #acoustic-attack #side-channel #privacy #karstorat #keystroke-recovery #surveillance #hardware-security

Your laptop is literally listening to you type. This isn’t a thought experiment. Recent research shows that the microphone built into your machine can be used to recover what you are typing with accuracy high enough to actually matter.

The numbers are uncomfortable. Researchers demonstrated keystroke recovery from laptop audio hitting roughly 85% accuracy. When you add Transformer models to fill in the noise, that figure climbs to 95%. This isn’t just for mechanical keyboards either. It works on the chiclet keys most of us use daily.

Here is the kicker: it works over video calls. If you type during a Zoom meeting, the clicks your microphone picks up can be used by anyone on that call to reconstruct what you wrote. Your password manager won’t save you if you type credentials while sharing audio.

And it is not just sound. Electromagnetic side-channel attacks on smartphones have broken ECDSA encryption by analyzing emissions from the device. Your phone physically leaks signals during crypto operations. These leaks carry enough info to recover keys. The assumption that an air-gapped or disconnected device is safe needs to be retired. Physical privacy is now a real discipline, and your keyboard is talking louder than you think.

Learn why muted mics and webcam covers are now mandatory for security