STIGQter: STIG Summary: Microsoft Office 365 ProPlus Security Technical Implementation Guide Version: 2 Release: 2 Benchmark Date: 23 Apr 2021:

Trust Bar notification must be enabled for unsigned application add-ins in Excel and blocked.

DISA Rule

SV-223337r508019_rule

Vulnerability Number

V-223337

Group Title

SRG-APP-000131

Rule Version

O365-EX-000028

Severity

CAT II

CCI(s)

• CCI-001749 - 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.

Weight

10

Fix Recommendation

Set policy value for User Configuration >> Administrative Templates >> Microsoft Excel 2016 >> Excel Options >> Security >> Trust Center >> Disable Trust Bar Notification for unsigned application add-ins and block them to "Enabled".

Check Contents

Verify the policy value for User Configuration >> Administrative Templates >> Microsoft Excel 2016 >> Excel Options >> 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\excel\security

If the value for notbpromptunsignedaddin is REG_DWORD = 1, this is not a finding.

Vulnerability Number

V-223337

Documentable

False

Rule Version

O365-EX-000028

Severity Override Guidance

Verify the policy value for User Configuration >> Administrative Templates >> Microsoft Excel 2016 >> Excel Options >> 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\excel\security

If the value for notbpromptunsignedaddin is REG_DWORD = 1, this is not a finding.

Check Content Reference

M

Target Key

4099

Comments