CovertBand, a sonar-based attack, is the product of four researchers work at the University of Washingtons Paul G. Allen School of Computer Science & Engineering. Attackers could use sonar to infer information about what a target is doing, including when they might be engaging in sexual activity. With two microphones picking up the transmissions, an attacker can receive the recorded data over Bluetooth and approximate a target’s 2D positioning using a laptop. The researchers had Bob walk around inside of a bathroom and do several activities, including brushing his teeth and sitting on the toilet.”]
Source: https://grahamcluley.com/sonar-based-attack-could-help-hackers-infer-when-youre-having-sex/