Regarding firewall stuff, disable it on your machine and you are fine.

How do you know OP doesn’t have a bunch of unsecured services sticking out into their LAN ready to be a target for the next cryptolocking scam?

Slightly sarcastic, but yeah, OP, do not just turn your firewall without understanding pros and cons of doing such. At the very least, see what your server exposes to the network (ss -tunlp will give you a good starting point), and see if there’s nothing unexpected in there that might be abused.