ARDC-CL-000320 - Adobe Reader DC must disable the ability to specify Host-Based Privileged Locations.
Privileged Locations allow the user to selectively trust files, folders, and hosts to bypass some security restrictions, such as enhanced security and protected view. By default, the user can create privileged locations through the GUI. Disabling Host-Based Privileged Locations disables and locks the end user's ability to add hosts as a privileged location prevents them from assigning trust and thereby exempting that location from enhanced security restrictions.
Configure the following registry value: Registry Hive: HKEY_LOCAL_MACHINE Registry Path: \Software\Policies\Adobe\Acrobat Reader\2015\FeatureLockDown Value Name: bDisableTrustedSites Type: REG_DWORD Value: 1