As reported by the Nightwatch Cybersecurity, there is a newly found hole in the security of every Android OS older than 9 Pie. This gap allows a potential hacker to learn your phone’s IP and MAC address, Wi-Fi and BSSID, giving them the possibility to, among other things, track your position and enter your Wi-Fi network. Google knows the issue and is working on fixing it, but so far only Android 9 Pie devices are safe. For everyone with older OS, be extra careful: no opening mails from Nigerian princes, no clicking on ads etc.