Trust Bar Notifications for unsigned application add-ins in Access must be disabled and blocked. (Cat II impact)
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.
Verify the policy value for User Configuration >> Administrative Templates >> Microsoft Access 2016 >> Application Settings >> Security >> Trust Center "Disable Trust Bar Notification for unsigned application add-ins and block them" is set to "Enabled". Use the Windows Registry Editor to navigate to the following key: HKCU\Software\Policies\Microsoft\Office\16.0\access\security If the value NoTBPromptUnsignedAddin is REG_DWORD = 1, this is not a finding.
Set the policy value for User Configuration >> Administrative Templates >> Microsoft Access 2016 >> Application Settings >> Security >> Trust Center "Disable Trust Bar Notification for unsigned application add-ins and block them" to "Enabled".
Rule ID: SV-223281r879584_rule
Vulnerability ID: V-223281
Group Title: SRG-APP-000131
The information system prevents the installation of organization-defined software components without verification the software component has been digitally signed using a certificate that is recognized and approved by the organization.