APPL-12-000032 - The macOS system must be configured with dedicated user accounts to decrypt the hard disk upon startup - UserShell
Information
When 'FileVault' and Multifactor Authentication are configured on the operating system, a dedicated user must be configured to ensure that the implemented Multifactor Authentication rules are enforced. If a dedicated user is not configured to decrypt the hard disk upon startup, the system will allow a user to bypass Multifactor Authentication rules during initial startup and first login.Solution
Note: In previous versions of macOS, this setting was implemented differently. Systems that used the previous method should prepare the system for the new method by creating a new unlock user, verifying its ability to unlock FileVault after reboot, then deleting the old FileVault unlock user.Disable the login ability of the newly created user account:
$ sudo /usr/bin/dscl . change /Users/<FileVault_User> UserShell </path/to/current/shell> /usr/bin/false
Remove all FileVault login access from each user account defined on the system that is not a designated FileVault user:
$ sudo fdesetup remove -user <username>
See Also
https://dl.dod.cyber.mil/wp-content/uploads/stigs/zip/U_Apple_macOS_12_V1R4_STIG.zip
Item Details
Audit Name: DISA STIG Apple macOS 12 v1r4
Category: ACCESS CONTROL
References: 800-53|AC-2(11), CAT|II, CCI|CCI-002143, Rule-ID|SV-252454r853262_rule, STIG-ID|APPL-12-000032, Vuln-ID|V-252454
Plugin: Unix
Control ID: 3d8e9d62d5f76b25ede56ec961ee5b34f3c77ec097b29b696d5151efd399dec0