The macOS system must disable logon to other user's active and locked sessions.

The ability to log in to another user's active or locked session must be disabled.

macOS has a privilege that can be granted to any user that will allow that user to unlock active user's sessions. Disabling the admins and/or user's ability to log into another user's active and locked session prevents unauthorized persons from viewing potentially sensitive and/or personal information.

Note: Configuring this setting will disable TouchID from unlocking the screensaver.

Verify the macOS system is configured to disable login to other user's active and locked sessions with the following command:

/usr/bin/security authorizationdb read system.login.screensaver 2>&1 | /usr/bin/grep -c '<string>authenticate-session-owner</string>'

If the result is not "1", this is a finding.

Configure the macOS system to disable login to other user's active and locked sessions with the following command:

/usr/bin/security authorizationdb write system.login.screensaver "authenticate-session-owner"