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 the operating system disables the ability to automount devices.

Check to see if automounter service is active with the following command:

# systemctl status autofs
autofs.service - Automounts filesystems on demand
Loaded: loaded (/usr/lib/systemd/system/autofs.service; disabled)
Active: inactive (dead)

If the "autofs" status is set to "active" and is not documented with the Information System Security Officer (ISSO) as an operational requirement, this is a finding.

Fix

Configure the operating system to disable the ability to automount devices.

Turn off the automount service with the following commands:

# systemctl stop autofs
# systemctl disable autofs

If "autofs" is required for Network File System (NFS), it must be documented with the ISSO.