9.4.7 Connecting to a remote X server –
xhost allows access based on hostnames. This is very insecure.
The following will disable host checking and allow connections from anywhere if
a TCP/IP socket connection is allowed (see
Using X over
TCP/IP, Section 9.4.6):
$ xhost +
You can re-enable host checking with:
$ xhost -
xhost does not distinguish between different users on the remote
host. Also, hostnames (addresses actually) can be spoofed.
This method must be avoided even with more restrictive host criteria if you're
on an untrusted network (for instance with dial-up PPP access to the Internet).