Information
The operating system must be configured so that remote X connections for interactive users are encrypted.
Rationale:
Open X displays allow an attacker to capture keystrokes and execute commands remotely.
Solution
Configure SSH to encrypt connections for interactive users.
Edit the /etc/ssh/sshd_config file to uncomment or add the line for the X11Forwarding keyword and set its value to yes (this file may be named differently or be in a different location if using a version of SSH that is provided by a third-party vendor):
Example: vim /etc/ssh/sshd_config
Add, uncomment or update the following line:
X11Forwarding yes
The SSH service must be restarted for changes to take effect:
# systemctl restart sshd
Notes:
This Benchmark recommendation maps to:
Red Hat Enterprise Linux 7 Security Technical Implementation Guide:
Version 2, Release: 3 Benchmark Date: 26 Apr 2019
Vul ID: V-72303
Rule ID: SV-86927r4_rule
STIG ID: RHEL-07-040710
Severity: CAT I