The Add-In Trust Level must be configured.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-228436	DTOO236	SV-228436r508021_rule		Medium

Description

All installed trusted COM addins can be trusted. Exchange Settings for the addins still override if present and this option is selected.

STIG	Date
Microsoft Outlook 2016 Security Technical Implementation Guide	2022-03-11

Details

Check Text (C-30669r497630_chk)

Verify the policy value for User Configuration -> Administrative Templates -> Microsoft Outlook 2016 -> Security "Configure Add-In Trust Level" is set to "Enabled (Trust all loaded and installed COM addins)".

Procedure: Use the Windows Registry Editor to navigate to the following key:

HKCU\Software\Policies\Microsoft\Office\16.0\outlook\security

Criteria: If the value AddinTrust is REG_DWORD = 1, this is not a finding.

Fix Text (F-30654r497631_fix)

Set the policy value for User Configuration -> Administrative Templates -> Microsoft Outlook 2016 -> Security "Configure Add-In Trust Level" to "Enabled (Trust all loaded and installed COM addins)".