Are there any international rules against firing ballistic missiles over other countries?
The BBC reports that (for the 2nd time since 2017) "North Korea fires ballistic missile over Japan". The missile fell into the Pacific ocean.
I'm guessing there are some treaties on the maximum height national airspace extends to, otherwise countries (which do have such ASAT capabilities) would be shooting down unfriendly spy satellites above their territory all the time.
So, what are the internationally accepted rules for ballistic missiles' trajectories?