edit: just reread the question. I missed the word "rooted" here. I actually have no clue, feel free to ignore this post.
I'd recommend running nmap (you have to install it):
And closing ports you don't use. For example if you see cups listening, and you don't use a printer, then uninstall cups (or disable it, probably with systemctl disable cupsd, if i remember correctly). You can also check your router settings to make sure no ports are being forwarded and the firewall is on, and make sure it's a reasonably secure operating system with
Code:
sudo nmap -O 192.168.0.1
And if you're still paranoid, look into managing iptables and checking your logs (probably with journalctl).