VBA macros are a common way for malicious actors to gain access to deploy malware and ransomware. To help improve security, Microsoft is changing the behavior of Office applications to now block macros in files from the internet.
This change only affects Office on devices running Windows and only affects the following applications: Access, Excel, PowerPoint, Visio, and Word.
Previously, it was possible for end-users to enable these macros by simply clicking a button on the Trust bar.
Now, with this change, once a user opens an attachment or downloads from the internet an untrusted Office file containing macros, a message bar displays a Security Risk that the file contains VBA macros obtained from the internet with a Learn More button.
The Learn More button goes to an article for end users and information workers that contains information about the security risk of bad actors using macros, safe practices to prevent phishing and malware, and instructions on how to enable these macros (if absolutely needed).
Enterprises should evaluate their use of macros in files obtained from the internet to determine how this new default behavior will affect your users.