AlmaLinux OS 9 must prevent a user from overriding the disabling of the graphical user interface automount function.

Severity	Group ID	Group Title	Version	Rule ID	Date	STIG Version
medium	V-269378	SRG-OS-000378-GPOS-00163	ALMA-09-035000	SV-269378r1050261_rule	2025-02-20	1

Description
Automatically mounting file systems permits easy introduction of unknown devices, thereby facilitating malicious activity. Satisfies: SRG-OS-000378-GPOS-00163, SRG-OS-000114-GPOS-00059

ℹ️ Check
Note: This requirement assumes the use of the AlmaLinux OS 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. Verify AlmaLinux OS 9 disables ability of the user to override the graphical user interface automount setting. Determine which profile the system database is using with the following command: $ grep system-db /etc/dconf/profile/user system-db:local Check that the automount setting is locked from nonprivileged user modification with the following command: Note: The example below is using the database "local" for the system, so the path is "/etc/dconf/db/local.d". This path must be modified if a database other than "local" is being used. $ grep 'automount-open' /etc/dconf/db/local.d/locks/* /org/gnome/desktop/media-handling/automount-open If the command does not return at least the example result, this is a finding.

ℹ️ Check

Note: This requirement assumes the use of the AlmaLinux OS 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. Verify AlmaLinux OS 9 disables ability of the user to override the graphical user interface automount setting. Determine which profile the system database is using with the following command: $ grep system-db /etc/dconf/profile/user system-db:local Check that the automount setting is locked from nonprivileged user modification with the following command: Note: The example below is using the database "local" for the system, so the path is "/etc/dconf/db/local.d". This path must be modified if a database other than "local" is being used. $ grep 'automount-open' /etc/dconf/db/local.d/locks/* /org/gnome/desktop/media-handling/automount-open If the command does not return at least the example result, this is a finding.

✔️ Fix
Configure the GNOME desktop to not allow a user to change the setting that disables automated mounting of removable media. Add the following line to "/etc/dconf/db/local.d/locks/00-security-settings-lock" to prevent user modification: /org/gnome/desktop/media-handling/automount-open Then update the dconf system databases: $ dconf update