This reminds me of "crackit"[0] from a few years ago with Redis. A lot of folks kept their Redis server bound to 0.0.0.0 with no firewall or published port 6379 by "accident" with Docker and by default Redis uses no password. It was a lot worse than meow because with some Redis configuration magic anyone could inject their own SSH keys onto the server.
This article says Redis is affected but I would be curious to see which version of Redis was being used because they changed their default configuration after crackit was wide spread.