Your home router already broadcasts enough data to map and recognize people. ISP gear adds extra features and company access. Switching to your own hardware removes that layer.
WiFi signals could potentially be used to identify people and map their surroundings without relying on cameras or requiring the person being observed to carry a connected device.
“By observing the propagation of radio waves, we can create an image of the surroundings and of persons who are present,” says Professor Thorsten Strufe from KASTEL, KIT’s Institute of Information Security and Dependability. “This works similar to a normal camera, the difference being that in our case, radio waves instead of light waves are used for the recognition,” explains the cybersecurity expert.
Because the technique analyzes radio waves moving through a space, a person does not need to have a phone, smartwatch, or other WiFi enabled device with them. “Thus, it does not matter whether you carry a WiFi device on you or not.”
Even turning off your own device would not necessarily prevent the system from working. “It’s sufficient that other WiFi devices in your surroundings are active.”
https://www.sciencedaily.com/releases/2026/08/260811052857.htm
Comcast rolled out WiFi Motion detection on millions of Xfinity gateways this month.
Policy allows sharing motion data with third parties under certain conditions.
Earlier Russian router compromises showed how easily ISP and consumer devices get weaponized.
Researchers push for built-in privacy fixes before the capability becomes widespread.
The spy who came in from the WiFi
https://www.kit.edu/kit/english/pi_2025_069_the-spy-who-came-in-from-the-wifi-beware-of-radio-network-surveillance.php