Vulnerability Discussion
Automatically mounting file systems permits easy introduction of unknown devices, thereby facilitating malicious activity.
Satisfies: SRG-OS-000114-GPOS-00059, SRG-OS-000378-GPOS-00163, SRG-OS-000480-GPOS-00227
Check
Verify RHEL 9 disables the graphical user interface automount function with the following command:
Note: This requirement assumes the use of the RHEL 9 default graphical user interface, the GNOME desktop environment. If the system does not have any graphical user interface installed, this requirement is Not Applicable.
$ gsettings get org.gnome.desktop.media-handling automount-open
false
If "automount-open" is set to "true", and is not documented with the information system security officer (ISSO) as an operational requirement, this is a finding.
Fix
Configure the GNOME desktop to disable automated mounting of removable media.
The dconf settings can be edited in the /etc/dconf/db/* location.
Update the [org/gnome/desktop/media-handling] section of the "/etc/dconf/db/local.d/00-security-settings" database file and add or update the following lines:
[org/gnome/desktop/media-handling]
automount-open=false
Then update the dconf system databases:
$ sudo dconf update