TMA-OFFICE-2.2.4.7.2.3.2

Ensure 'Do not open files from the internet zone in Protected View' is set to 'Disabled'

HighLevel 1Automatedoffice

Description

This policy setting determines whether files downloaded from the Internet zone open in Protected View. The recommended state for this setting is: Disabled. Rationale: Allowing users to download files from the Internet zone to open outside of Protected View could allow malicious code to become active on a user's computer or the network. User setting: the audit checks HKEY_USERS\<SID>\SOFTWARE\Policies\Microsoft\office\16.0\excel\security\protectedview:disableinternetfilesinpv (REG_DWORD) in every loaded user hive (S-1-5-21-*) and is compliant when each holds 0. It prints 'no-user-hive-loaded' (FAIL) when no user profile is loaded, so scan while users are logged on.

How it is checked

Audit method: Windows registry

registry

$sids = @(Get-ChildItem -Path 'Registry::HKEY_USERS' -ErrorAction SilentlyContinue | Where-Object { $_.PSChildName -match '^S-1-5-21-\d+-\d+-\d+-\d+$' } | ForEach-Object { $_.PSChildName }); if ($sids.Count -eq 0) { 'no-user-hive-loaded' } else { $bad = @(); foreach ($s in $sids) { $v = (Get-ItemProperty -Path ('Registry::HKEY_USERS\' + $s + '\SOFTWARE\Policies\Microsoft\office\16.0\excel\security\protectedview') -Name 'disableinternetfilesinpv' -ErrorAction SilentlyContinue).'disableinternetfilesinpv'; if (-not ($null -ne $v -and @(0) -contains [int64]$v)) { $bad += $s + ':disableinternetfilesinpv=' + $v } }; if ($bad.Count -eq 0) { 'compliant' } else { 'non-compliant: ' + ($bad -join ', ') } }

Expected output: compliant

How it is fixed

Fix method: Guidance or infrastructure patch

Configure through Group Policy (User Configuration): User Configuration\Administrative Templates\Microsoft Excel 2016\Excel Options\Security\Trust Center\Protected View\Do not open files from the internet zone in Protected View = Disabled

Properties

Operating systems: Any
Tags: officeproductivitycis-l1
Reference: CIS Microsoft Office Enterprise Benchmark v2.0.0 - 2.2.4.7.2.3.2 Ensure 'Do not open files from the internet zone in Protected View' is set to 'Disabled'

Check this host

Run this on a machine you are allowed to audit. The scan is read-only.

shell

tmaegis scan --target office