Posted by ClydeDev on 09/14/05 08:42

I suppose this may be a simple question, but I did a port scan on my
Linksys router and found about 20 open UDP ports, along with the open
TCP ports that I configured for port forwarding. My question is, how
can these UDP ports be open to the outside world if I have not
specificly given the router permission to forward these ports?
Theoreticly, if I run FTP(21),SHH(22), & HTTP(80) on a server, but only
forward port 80, that will be the only open port when doing a port
scan... even though port 21 & 22 are open and listening on that given
box. Now, I know my theory is based on TCP ports, and I'm asking about
UDP ports, but I'm assuming the Linksys router/firewall should be
blocking everything, and only allowing what I permit.
I'd appreciate any insight into this matter, and ask that all replies
be cc: to my personal email.
Thank you.

Frank Baris
frank AT clydedevelopment.com

[Back to original message]