Hacker News new | ask | show | jobs
by pyronik19 505 days ago
Would there be a way for the bluetooth device to rotate its broadcast keys in a predictable way to avoid the iphone notification of "unknown airtag close by" messages? Seems like this could be exploited for surveillance.
3 comments

Yes, the FindYou project [0] has shown this to be possible.

[0] https://github.com/positive-security/find-you

Sure, that works.

One can also just cycle through a sufficiently large bank of pre-allocated keys, such that a findmy receiver doesn't see the same key too frequently.

You just need to derive a new key, this process is already part of the protocol to avoid being tracked while you wear your airtag
Technically it would need to rotate every 15 minutes or so - the notification you're talking about happens when the device is in "lost mode" (away from its owner): in that case the key is rotate every 24 hours