Information
This policy setting controls whether macros can run in an Office application that is opened programmatically by another application. The recommended state for this setting is: Enabled. (Disable Macros by Default) By default, when a separate program is used to launch Microsoft Office Excel, PowerPoint, or Word programmatically, any macros can run in the programmatically opened application without being blocked. This functionality could allow an attacker to use automation to run malicious code in Excel, PowerPoint, or Word.
Solution
To implement the recommended configuration state, set the following Group Policy setting to Enabled. User Configuration\Administrative Templates\Microsoft Office 2013\Security Settings\Automation Security Impact: Enabling this setting and selecting 'Disable macros by default' from the drop-down menu could limit functionality if an external application programmatically opens a Office application to open a document or template containing macros.