As it turns out, you do not even need cell site simulators / false base station to do IMSI catching.
In my research, I developed a technique to attack a phone with low power from km away, without being able to be detected at all with traditional tools like SeaGlass or Crocodile Hunter. It‘s published here and works against production LTE networks, no downgrade attacks whatsoever necessary:
In my research, I developed a technique to attack a phone with low power from km away, without being able to be detected at all with traditional tools like SeaGlass or Crocodile Hunter. It‘s published here and works against production LTE networks, no downgrade attacks whatsoever necessary:
https://dl.acm.org/doi/10.1145/3495243.3560525