Trust Bar Notifications for unsigned application add-ins must be blocked.

Severity
Group ID
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Version
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STIG Version
mediumV-70719SRG-APP-000131DTOO131SV-85343r1_rule2016-11-021
Description
This policy setting controls whether the specified Office application notifies users when unsigned application add-ins are loaded or silently disable such add-ins without notification. This policy setting only applies if you enable the "Require that application add-ins are signed by Trusted Publisher" policy setting, which prevents users from changing this policy setting. If you enable this policy setting, applications automatically disable unsigned add-ins without informing users. If you disable this policy setting, if this application is configured to require that all add-ins be signed by a trusted publisher, any unsigned add-ins the application loads will be disabled and the application will display the Trust Bar at the top of the active window. The Trust Bar contains a message that informs users about the unsigned add-in. If you do not configure this policy setting, the disable behavior applies, and in addition, users can configure this requirement themselves in the "Add-ins" category of the Trust Center for the application.
ℹ️ Check
Verify the policy value for User Configuration -> Administrative Templates -> Microsoft Project 2016 -> Project Options -> Security -> Trust Center -> "Disable Trust Bar Notification for unsigned application add-ins and block them" is set to "Enabled". Procedure: Use the Windows Registry Editor to navigate to the following key: HKCU\software\policies\Microsoft\office\16.0\ms project\security Criteria: If the value notbpromptunsignedaddin is REG_DWORD = 1, this is not a finding.
✔️ Fix
Set the policy value for User Configuration -> Administrative Templates -> Microsoft Project 2016 -> Project Options -> Security -> Trust Center -> "Disable Trust Bar Notification for unsigned application add-ins and block them" to "Enabled".