Why Your Wi-Fi Router Doubles as an Apple AirTag

University of Maryland researchers demonstrated that Apple’s Wi‑Fi-based Positioning System returns large sets of geolocated BSSIDs when queried, allowing them to map billions of Wi‑Fi access points globally and to geofence areas to track device movement — including Starlink terminals used in the Ukraine and Gaza conflicts — exposing troop movements, refugee relocations and individual locations. The paper highlights significant privacy and safety risks, notes that researchers disclosed findings to Apple and Starlink, and records mitigations: Starlink rolled out BSSID randomization and Apple publicized an opt-out (_nomap) for SSIDs and is being urged to rate-limit or further restrict its API.