October 17, 2025, 2:03 pm | Read time: 2 minutes
Wi-Fi can be used as a spy, as a new investigation has revealed. No special technology or camera is needed for this.
The security of wireless networks is increasingly coming into focus, as new investigations show how easily they can be exploited for surveillance. A recent study by the Karlsruhe Institute of Technology (KIT) reveals that with minimal technical effort, individuals in a room can be identified. These findings raise questions about privacy and call for protective measures.
Wi-Fi as a Spy
Routers and smartphones continuously communicate to optimize their connection. In doing so, they send so-called beamforming data, which is unencrypted. An AI system can use this data to analyze radio waves in the room and create a kind of shadow image that makes individuals distinguishable. In this way, the system turns Wi-Fi into a spy.
In a test with 197 participants, the researchers achieved an almost 100 percent recognition rate. Thorsten Strufe from KIT explains: “It is enough if there is an active Wi-Fi device somewhere.” This means that theoretically, any router could become a surveillance source.
Challenges for Privacy
Particularly concerning is that this technology does not require expensive special hardware. Standard routers and laptops are sufficient to generate and receive the necessary data. This makes the method difficult to detect and stop.
To protect privacy, researchers at KIT are calling for the introduction of new Wi-Fi standards with protective mechanisms. These could include encryption or restrictions on unprotected feedback data to prevent unnoticed surveillance.