server crash when raising/lowering anchor

I had this bug twice. the first time, I was near cookie cutters and salt formations, and while I was a little bit distracted from the game, I think my server crashed as I lowered my anchor.
The second time, I was sailing in a random spot in the ocean next to a floating bottle, and I crashed as I was raising my anchor.

Here's a log from the first time (the second time it was the same error).server_log.txt