VBA Macros not digitally signed must be blocked in Word.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-223417	O365-WD-000018	SV-223417r928385_rule		Medium

Description
This policy setting controls how the specified applications warn users when Visual Basic for Applications (VBA) macros are present. If you enable this policy setting, you can choose from four options for determining how the specified applications will warn the user about macros: - Disable all with notification: The application displays the Trust Bar for all macros, whether signed or unsigned. This option enforces the default configuration in Office. This option also allows users to potentially enable unsigned/untrusted macros. If a site requires the use of macros, they must be signed /approved and added to appropriate locations listed in the Trust Center Settings. - Disable all except digitally signed macros: The application displays the Trust Bar for digitally signed macros, allowing users to enable them or leave them disabled. Any unsigned macros are disabled, and users are not notified. - Disable all without notification: The application disables all macros, whether signed or unsigned, and does not notify users. - Enable all macros (not recommended): All macros are enabled, whether signed or unsigned. This option can significantly reduce security by allowing dangerous code to run undetected.

Description

This policy setting controls how the specified applications warn users when Visual Basic for Applications (VBA) macros are present. If you enable this policy setting, you can choose from four options for determining how the specified applications will warn the user about macros: - Disable all with notification: The application displays the Trust Bar for all macros, whether signed or unsigned. This option enforces the default configuration in Office. This option also allows users to potentially enable unsigned/untrusted macros. If a site requires the use of macros, they must be signed /approved and added to appropriate locations listed in the Trust Center Settings. - Disable all except digitally signed macros: The application displays the Trust Bar for digitally signed macros, allowing users to enable them or leave them disabled. Any unsigned macros are disabled, and users are not notified. - Disable all without notification: The application disables all macros, whether signed or unsigned, and does not notify users. - Enable all macros (not recommended): All macros are enabled, whether signed or unsigned. This option can significantly reduce security by allowing dangerous code to run undetected.

STIG	Date
Microsoft Office 365 ProPlus Security Technical Implementation Guide	2024-02-21

Details

Check Text ( C-25090r928384_chk )
Verify the policy value for User Configuration >> Administrative Templates >> Microsoft Word 2016 >> Security >> Trust Center >> "VBA macro Notification Settings" is set to "Enabled" and "Disable all except digitally signed macros" from the Options. Use the Windows Registry Editor to navigate to the following key: HKCU\software\policies\Microsoft\office\16.0\word\security If the value vbawarnings is REG_DWORD = 3, this is not a finding. A value of REG_DWORD = 4 is also acceptable. If the registry key does not exist or is not configured properly, this is a finding.

Check Text ( C-25090r928384_chk )

Verify the policy value for User Configuration >> Administrative Templates >> Microsoft Word 2016 >> Security >> Trust Center >> "VBA macro Notification Settings" is set to "Enabled" and "Disable all except digitally signed macros" from the Options.

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

HKCU\software\policies\Microsoft\office\16.0\word\security

If the value vbawarnings is REG_DWORD = 3, this is not a finding. A value of REG_DWORD = 4 is also acceptable. If the registry key does not exist or is not configured properly, this is a finding.

Fix Text (F-25078r442471_fix)
Set the policy value for User Configuration >> Administrative Templates >> Microsoft Word 2016 >> Security >> Trust Center >> "VBA macro Notification Settings" to "Enabled" and "Disable all except digitally signed macros" from the Options.