xauth

If you are using the X server, this command will display and edit the authorization information.

If you use the list option you will be able to view the current magic cookie. The significance of the magic cookie is that it will be needed as a security measure to view your X Window remotely. There are two magic cookies that are viewed with this command. The first is the inet domain and the second is the unix domain.

mike@ub:~$ xauth list

ub/unix:0 MIT-MAGIC-COOKIE-1 951bd6024bb75bfb5ecfc413e3f613c2

localhost.localdomain/unix:0 MIT-MAGIC-COOKIE-1 951bd6024bb75bfb5ecfc413e3f613c2

Now if you copy the inet domain magic cookie and then log into a remote machine you need to:

set env DISPLAY local.machine:0

Then insert the magic cookie with this command:

xauth add <paste in the magic cookie>

Now you should have remote access to the Xwindow. Seeing how easy this may be done gives you good reason to block ports 6000-6007 which are used by the Xwindow.