Running 1.27 server under Debian bookworm and loading some object spawner loader json I found on the internet resulted after some minutes! in one of the infamous *stack smashing detected* crashes.
Investigating the file showed one object being placed outside of the world.
As this is something that could easily happen and there is no sane way to find the bug except for spending some hours with git-bisect, I think you should ensure that when placing objects in the world they are placed in a sane location and instead of crashing filter them out and create an appropriate error message.