When flying into specific chunks on my server, or into the same world copied to a local, vanilla instance of Minecraft, the server permanently stops responding, timing out all connected clients (though they appear to remain connected indefinitely according to the server). The area in question (somewhere between (2188, 941) and (2342, 1877) consistently causes a hang which seems to be related to the server filling in the new lower subchunks with 1.18 cave generation. There are several ungenerated chunks in this region as it is near the edge of generated terrain, visible in the MCA Selector screenshot attached. This world was originally generated in Minecraft 1.14.4 (using seed 6698898227542038432) and has been active since then and upgraded through every major release. It has never been used with any snapshots.

World files are available on request; they are 4.4 GB in size and are currently still uploading to a server.

What I expected to happen was...:
The game to continue as normal.

What actually happened was...:
Server permanently hangs and all clients are disconnected; server must be killed in order to restart it.

Steps to Reproduce:
1. Spawn into world
2. Fly in survival mode using elytra and riptide trident to south-southeast over frozen ocean biome roughly toward the coordinates (2253, 1224) - speed of flight does not appear to matter, even approaching cautiously can cause a freeze.
3. Somewhere near this area the server will hang; in a local vanilla Minecraft client/server this manifests as the world ceasing to update properly and the player no longer animating correctly.