cybersecurity

Potentially misunderstanding but that's exactly what this is, right?

You recorded the code for a given unlock (I'm assuming out of range of the vehicle), replayed it, the car then rolled the code on to the next one and your replayed code was no longer valid and your existing fob didn't know to rollover too, so was left out of sync.

So yes I guess there's the risk it hasn't been implemented correctly, but adds the necessary functionality you were missing to accomplish this before.

Though it would still leave the fob out of sync, in theory I feel like it could be possible for the flipper to send the necessary information to allow the fob to be resynchronised too. Of course someone would need to write this functionally

So you’re saying if you don’t like someone you can unlock their car once. Sit back as they have a shitty day and are forced to replace their key fob.

Then you can unlock their car one more time and their shitty day repeats itself.

No, this would still desync your key. You in theory could maybe figure out how to pair it to your car as a spare fob, depending on what rolling codes fiat uses or how that pairing process works on fiats, but you'd have to set it up like that to not desync your regular fob.