The Red Hat Enterprise Linux operating system must be configured so that remote X connections for interactive users are encrypted.

From Red Hat Enterprise Linux 7 Security Technical Implementation Guide

Associated with: CCI-000366

SV-86927r4_rule The Red Hat Enterprise Linux operating system must be configured so that remote X connections for interactive users are encrypted.

Vulnerability discussion

Open X displays allow an attacker to capture keystrokes and execute commands remotely.

Check content

Verify remote X connections for interactive users are encrypted. Check that remote X connections are encrypted with the following command: # grep -i x11forwarding /etc/ssh/sshd_config | grep -v "^#" X11Forwarding yes If the "X11Forwarding" keyword is set to "no" or is missing, this is a finding.

Fix text

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): X11Forwarding yes The SSH service must be restarted for changes to take effect: # systemctl restart sshd

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