1.64 SOL-11.1-020530

Information

X displays must not be exported to the world.

GROUP ID: V-216311
RULE ID: SV-216311r959010

Open X displays allow an attacker to capture keystrokes and to execute commands remotely. Many users have their X Server set to xhost +, permitting access to the X Server by anyone, from anywhere.

Solution

If using an xhost-type authentication the xhost - command can be used to remove current trusted hosts and then selectively allow only trusted hosts to connect with xhost + commands. A cryptographically secure authentication, such as provided by the xauth program, is always preferred. Refer to your X11 server's documentation for further security information.

See Also

https://workbench.cisecurity.org/benchmarks/23765