Airtag was launched two weeks ago and is being fully analyzed by security researchers. The small tray has the potential to be very useful for finding belongings, but any safety deficiencies can also be serious as the tray is so cheap and can be expected to be sold in large volumes.
Earlier this week, Thomas Roth (Stacksmashing) unveiled a hack of Airtag’s nfc chip that makes it possible to change the URL displayed when someone is holding an nfc-equipped mobile next to the tile, and now the Find Network itself has been used for a purpose other than that intended.
Fabian Bräunlein has programmed a microcontroller called Esp32 to send messages over the Apple Find network. By using the same encryption features that Airtags and other products with support for the Find network use, he shows how it is possible to send other than coordinates.
An Airtag in lost mode normally sends encrypted GPS coordinates over the Find network, that is, with the help of passing iPhones and other Apple gadgets. With Fabian Bräunlein’s technology, it is possible to encrypt other data, such as a short text message. A specially crafted Mac application can then receive and decrypt the messages.
The same technologies that make Airtag and the Find network secure mean that Apple will have a very hard time doing anything about this type of “theft”. The encryption system makes it impossible for Apple to see who a particular message is, or whether it really contains coordinates.