Information
To protect the on-screen content of a session, it must be replaced with a publicly-viewable pattern upon session lock. Examples of publicly viewable patterns include screen saver patterns, photographic images, solid colors, or a blank screen, so long as none of those patterns convey sensitive information. This requirement applies to graphical desktop environments provided by the system to locally attached displays and input devices, as well as, to graphical desktop environments provided to remote systems using remote access protocols.
NOTE: Nessus has not performed this query, and this check is only provided for informational purposes.
Solution
Configure the system to display a publicly-viewable pattern during a session lock. This is done graphically by selecting a screensaver theme using gnome-screensaver-preferences command. Any of the themes distributed with RHEL may be used including 'Blank Screen'.