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

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-17187	DTOO131 - Excel	SV-33442r1_rule	ECSC-1	Medium

Description
If an application is configured to require 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 informing users about the unsigned add-in.

STIG	Date
Microsoft Excel 2010	2014-01-07

Details

Check Text ( C-33925r1_chk )
The policy value for User Configuration -> Administrative Templates -> Microsoft Excel 2010 -> Excel Options -> Security -> Trust Center “Disable Trust Bar Notification for unsigned application add-ins and block them” must be “Enabled”. Procedure: Use the Windows Registry Editor to navigate to the following key: HKCU\Software\Policies\Microsoft\Office\14.0\excel\security Criteria: If the value NoTBPromptUnsignedAddin is REG_DWORD = 1, this is not a finding.

Check Text ( C-33925r1_chk )

The policy value for User Configuration -> Administrative Templates -> Microsoft Excel 2010 -> Excel Options -> Security -> Trust Center “Disable Trust Bar Notification for unsigned application add-ins and block them” must be “Enabled”.

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

HKCU\Software\Policies\Microsoft\Office\14.0\excel\security

Criteria: If the value NoTBPromptUnsignedAddin is REG_DWORD = 1, this is not a finding.

Fix Text (F-29614r1_fix)
Set the policy value for User Configuration -> Administrative Templates -> Microsoft Excel 2010 -> Excel Options -> Security -> Trust Center “Disable Trust Bar Notification for unsigned application add-ins and block them” to “Enabled”.