Vulnerability Discussion

A session time-out lock is a temporary action taken when a user stops work and moves away from the immediate physical vicinity of the information system but does not log out because of the temporary nature of the absence. Rather than relying on the user to manually lock their operating system session prior to vacating the vicinity, operating systems need to be able to identify when a user's session has idled and take action to initiate the session lock.

The session lock is implemented at the point where session activity can be determined and/or controlled.

Satisfies: SRG-OS-000029-GPOS-00010, SRG-OS-000031-GPOS-00012

Check

Note: This requirement assumes the use of the OL 8 default graphical user interface, Gnome Shell. If the system does not have any graphical user interface installed, this requirement is Not Applicable.

Verify the operating system initiates a session lock a for graphical user interfaces when the screensaver is activated with the following command:

$ sudo gsettings get org.gnome.desktop.screensaver lock-delay

uint32 5

If the "uint32" setting is missing, or is not set to "5" or less, this is a finding.

Fix

Configure the operating system to initiate a session lock for graphical user interfaces when a screensaver is activated.

Create a database to contain the system-wide screensaver settings (if it does not already exist) with the following command:

Note: The example below is using the database "local" for the system, so if the system is using another database in "/etc/dconf/profile/user", the file should be created under the appropriate subdirectory.

$ sudo touch /etc/dconf/db/local.d/00-screensaver

[org/gnome/desktop/screensaver]
lock-delay=uint32 5

The "uint32" must be included along with the integer key values as shown.

Update the system databases:

$ sudo dconf update