Security researchers have recently found a way to send data using the AirTag network without a way for Apple to prevent or monitor the exchange.
It’s now possible to subvert the Find My network and send messages between devices. However, AirTag users won’t have to worry about malware or be concerned about their devices’ security.

A blog post by Fabian Braunlein from Positive Security, an IT security consultancy firm in Berlin says that curiosity fueled the endeavor. Apparently, arbitrary data can be sent via Find My broadcasts, which is then picked up by Apple devices in the same manner as they get alerts when they come in close proximity to a lost AirTag.
In theory, a device could broadcast a signal that’s the same as an AirTag and have Apple devices pick it up even without WiFi, a data plan, SIM card or modem.
Positive Security also mentioned that the sixteen AirTag limit is cosmetic since Apple doesn’t have a way to enforce it.