1.7.2 Ensure GDM login banner is configured (Scored)
Profile Applicability
Level 1 - Server Level 1 - Workstation
Description
GDM is the GNOME Display Manager which handles graphical login for GNOME based systems.
Rationale
Warning messages inform users who are attempting to login to the system of their legal status regarding the system and must include the name of the organization that owns the system and any monitoring policies that are in place.
Audit
If GDM is installed on the system verify that /etc/dconf/profile/gdm
exists and contains the following:
user-db:user system-db:gdm file-db:/usr/share/gdm/greeter-dconf-defaults
Then verify the banner-message-enable
and banner-message-text
options are configured in /etc/dconf/db/gdm.d/01-banner-message
:
[org/gnome/login-screen] banner-message-enable=true banner-message-text='<banner message>'
Remediation
Create the /etc/dconf/profile/gdm
file with the following contents:
user-db:user system-db:gdm file-db:/usr/share/gdm/greeter-dconf-defaults
Create or edit the banner-message-enable
and banner-message-text
options in /etc/dconf/db/gdm.d/01-banner-message
:
[org/gnome/login-screen] banner-message-enable=true banner-message-text='Authorized uses only. All activity may be monitored and reported.'
Run the following command to update the system databases:
# dconf update
Notes
Additional options and sections may appear in the /etc/dconf/db/gdm.d/01-banner-message
file.
If a different GUI login service is in use, consult your documentation and apply an equivalent banner.