I'm quite a newbie with security-related things on linux, and just learning these... so I guess somebody has a simple answer to this question (hopefully
) which is related to a firewall based on iptables...
First of all, net-based tests (like the one at grc.com) show my ports as "stealth", but of course when I did a quick scan with nmap, it revealed my ports were all closed - except for one: port number 6000 (tcp), used by X11, was open. How's this possible? I've tried few times to get all the ports closed, but no - number 6000 isn't that easy, it just stays open no matter what I do.
So is there a way to get this damn port closed, or at least look like it? And why the heck is it open? Does X11 truly need an open port to work? Can't be...because if it is, then my X is going for a long walk with no return.
I also found that (at least in my opinion) grc-type test are quite easy to pass, but is there a way to get protected from scans like nmap? Was there or not, please tell me how I'll get my X11's open port closed.....
(please keep in mind I haven't played long with all these fwall, iptables, netfilters nor other related stuff...basically just read something about them and tried out for a small amount of time)
thanks for any help in advance