Title

ActiveX One-Off forms must be configured. (Cat II impact)

Discussion

By default, third-party ActiveX controls are not allowed to run in one-off forms in Outlook. You can change this behavior so that Safe Controls (Microsoft Forms 2.0 controls and the Outlook Recipient and Body controls) are allowed in one-off forms, or so that all ActiveX controls are allowed to run.

Check Content

Verify the policy value for User Configuration -> Administrative Templates -> Microsoft Outlook 2016 -> Security "Allow Active X One Off Forms" is set to "Enabled: Load only Outlook Controls". 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 AllowActiveXOneOffForms is REG_DWORD = 0, this is not a finding.

Fix Text

Set the policy value for User Configuration -> Administrative Templates -> Microsoft Outlook 2016 -> Security "Allow Active X One Off Forms" to "Enabled: Load only Outlook Controls".

Additional Identifiers

Rule ID: SV-228435r508021_rule

Vulnerability ID: V-228435

Group Title: SRG-APP-000210

Expert Comments

CCIs tied to check.

Controls tied to check. These are derived from the CCIs shown above.