The API service on Google Home and Chromecast devices before mid-July 2018 does not prevent DNS rebinding attacks from reading the scan_results JSON data, which allows remote attackers to determine the physical location of most web browsers by leveraging the presence of one of these devices on its local network, extracting the scan_results bssid fields, and sending these fields in a geolocation/v1/geolocate Google Maps Geolocation API request.