Is your router spying on you?
(Image credit: Linksys)
Researchers have identified a new Wi-Fi router security threatPeople in a space can be tracked using beamforming signalsNo physical access to the router is required to tap into its radio wavesResearchers from the Karlsruhe Institute of Technology in Germany have demonstrated how everyday Wi-Fi routers can be hacked and used as surveillance tools, using only the radio waves traveling from and back to the router.Here's how it works: routers using Wi-Fi 5 or later get feedback signals sent back to them from connected devices, known as Beamforming Feedback Information (BFI). The router uses this feedback to manage speeds and stability, but these messages are flowing freely through the air, and can be nabbed by other devices too.If someone physically passes through those signals, they get disrupted. The signal map isn't quite like a 3D map of a room, but the way the signals shift can act as a sort of signature for a person, based on how they walk and move through the space.Using some special software and a device with a Wi-Fi card (so a laptop, or a Raspberry Pi device for example), someone can monitor these BFI signals and check for disruption. As the signals are unencrypted, there's no need for physical access to the router, or the Wi-Fi password — the monitoring device just needs to be in the same physical space.Surveillance danger
