Setting the screensaver mode to blank-only conceals the contents of the display from passersby.
Check
Note: This requirement assumes the use of the RHEL 10 default graphical user interface, the GNOME desktop environment. If the system does not have any graphical user interface installed, this requirement is not applicable.
Verify RHEL 10 prevents a user from overriding settings a blank screensaver with the following command:
If "picture-uri" is writable, and the result is "true", this is a finding.
Fix
Configure RHEL 10 to prevent a user from overriding the picture-uri setting for graphical user interfaces.
Note: The example below is using the database "local" for the system. If the system is using another database in "/etc/dconf/profile/user", the file should be created under the appropriate subdirectory.
Update the "/etc/dconf/db/local.d/00-security-settings" file to prevent a user from overriding the "picture-uri" setting:
$ sudo vi /etc/dconf/db/local.d/00-security-settings
[org/gnome/desktop/screensaver] picture-uri=''
Update the "/etc/dconf/db/local.d/locks/00-security-settings-lock" file to prevent a user from modifying the lock applied to the "picture-uri" setting:
$ sudo vi /etc/dconf/db/local.d/locks/00-security-settings-lock