SV-223287r961863: Custom user interface (UI) code must be blocked from loading in all Office applications. | Microsoft Office 365 ProPlus STIG SCAP Benchmark

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Assessment Title

Rule Text

Custom user interface (UI) code must be blocked from loading in all Office applications.

Description

Discussion Text

This policy setting controls whether Office 365 ProPlus applications load any custom user interface (UI) code included with a document or template. Office 365 ProPlus allows developers to extend the UI with customization code that is included in a document or template. If this policy setting is enabled, Office 365 ProPlus applications cannot load any UI customization code included with documents and templates. If this policy setting is not configured or disabled, Office 365 ProPlus applications load any UI customization code included with a document or template when opening it.

How this relates to the STIG checklist: STIG vs SCAP benchmark.

IA Controls

NIST SP 800-53

Not mappedCCI-000366SV-108751V-99647

References

DPMS Target Microsoft Office 365 ProPlus DISA DPMS Target Microsoft Office 365 ProPlus 4099

SCC Automation Reference

The reconstructed evaluation script behind this rule's OVAL check(s) — every module a compound check combines, with this rule's own concrete values and DISA's SCC tool's real per-module mechanism curated from static teardown of SCC releases.

# Windows PowerShell
# Reconstructed from oval:mil.disa.stig.office365:def:223287
# Custom user interface (UI) code must be blocked from loading in all Office applications.
# Per-module read mechanism curated from static teardown of DISA's SCC tool
# (SCAP Compliance Checker) -- see the SCC Automation Reference above.
#
# MANUAL REVIEW REQUIRED -- the module(s) below could not be reconstructed
# into working code from curated SCC reference data, and are excluded from
# the automated result:
#   - ntuser_object (ntuser_test) -- Disable UI extending from documents and templates is set to 'Enabled' for Access: no extractor for field "type"
#   - ntuser_object (ntuser_test) -- Disable UI extending from documents and templates is set to 'Enabled' for Excel: no extractor for field "type"
#   - ntuser_object (ntuser_test) -- Disable UI extending from documents and templates is set to 'Enabled' for InfoPath: no extractor for field "type"
#   - ntuser_object (ntuser_test) -- Disable UI extending from documents and templates is set to 'Enabled' for Outlook: no extractor for field "type"
#   - ntuser_object (ntuser_test) -- Disable UI extending from documents and templates is set to 'Enabled' for PowerPoint: no extractor for field "type"
#   - ntuser_object (ntuser_test) -- Disable UI extending from documents and templates is set to 'Enabled' for Project: no extractor for field "type"
#   - ntuser_object (ntuser_test) -- Disable UI extending from documents and templates is set to 'Enabled' for Publisher: no extractor for field "type"
#   - ntuser_object (ntuser_test) -- Disable UI extending from documents and templates is set to 'Enabled' for Visio: no extractor for field "type"
#   - ntuser_object (ntuser_test) -- Disable UI extending from documents and templates is set to 'Enabled' for Word: no extractor for field "type"

# MS Access is installed.
# registry_object (registry_test)
function test_1 {
  return (($null -ne (Get-ItemProperty -Path 'Registry::HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Microsoft\Office\16.0\Access\InstallRoot' -Name 'Path')) -or ($null -ne (Get-ItemProperty -Path 'Registry::HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Office\16.0\Access\InstallRoot' -Name 'Path')))
}
# MS Excel is installed.
# registry_object (registry_test)
function test_3 {
  return (($null -ne (Get-ItemProperty -Path 'Registry::HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Microsoft\Office\16.0\Excel\InstallRoot' -Name 'Path')) -or ($null -ne (Get-ItemProperty -Path 'Registry::HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Office\16.0\Excel\InstallRoot' -Name 'Path')))
}
# Microsoft InfoPath 2013 is installed
# registry_object (registry_test)
function test_5 {
  return (($null -ne (Get-ItemProperty -Path 'Registry::HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Microsoft\Office\15.0\InfoPath\InstallRoot' -Name 'Path')) -or ($null -ne (Get-ItemProperty -Path 'Registry::HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Office\15.0\InfoPath\InstallRoot' -Name 'Path')))
}
# MS Outlook is installed.
# registry_object (registry_test)
function test_7 {
  return (($null -ne (Get-ItemProperty -Path 'Registry::HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Microsoft\Office\16.0\Outlook\InstallRoot' -Name 'Path')) -or ($null -ne (Get-ItemProperty -Path 'Registry::HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Office\16.0\Outlook\InstallRoot' -Name 'Path')))
}
# MS PowerPoint is installed.
# registry_object (registry_test)
function test_9 {
  return (($null -ne (Get-ItemProperty -Path 'Registry::HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Microsoft\Office\16.0\PowerPoint\InstallRoot' -Name 'Path')) -or ($null -ne (Get-ItemProperty -Path 'Registry::HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Office\16.0\PowerPoint\InstallRoot' -Name 'Path')))
}
# MS Project is installed.
# registry_object (registry_test)
function test_11 {
  return (($null -ne (Get-ItemProperty -Path 'Registry::HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Microsoft\Office\16.0\Project\InstallRoot' -Name 'Path')) -or ($null -ne (Get-ItemProperty -Path 'Registry::HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Office\16.0\Project\InstallRoot' -Name 'Path')))
}
# MS Publisher is installed.
# registry_object (registry_test)
function test_13 {
  return (($null -ne (Get-ItemProperty -Path 'Registry::HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Microsoft\Office\16.0\Publisher\InstallRoot' -Name 'Path')) -or ($null -ne (Get-ItemProperty -Path 'Registry::HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Office\16.0\Publisher\InstallRoot' -Name 'Path')))
}
# MS Visio is installed.
# registry_object (registry_test)
function test_15 {
  return (($null -ne (Get-ItemProperty -Path 'Registry::HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Microsoft\Office\16.0\Visio\InstallRoot' -Name 'Path')) -or ($null -ne (Get-ItemProperty -Path 'Registry::HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Office\16.0\Visio\InstallRoot' -Name 'Path')))
}
# MS Word is installed.
# registry_object (registry_test)
function test_17 {
  return (($null -ne (Get-ItemProperty -Path 'Registry::HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Microsoft\Office\16.0\Word\InstallRoot' -Name 'Path')) -or ($null -ne (Get-ItemProperty -Path 'Registry::HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Office\16.0\Word\InstallRoot' -Name 'Path')))
}

if ((test_1 -and test_3 -and test_5 -and test_7 -and test_9 -and test_11 -and test_13 -and test_15 -and test_17)) {
  Write-Output "PASS (automated portion only -- MANUAL REVIEW still required, see notes above)"
} else {
  Write-Output "FAIL (or see MANUAL REVIEW note above)"
}

Assessment Script Powered by AISyntax-verified

A standalone PowerShell script to assess this control automatically. Review before running it in your environment.

Syntax-checked as valid PowerShell. Not executed here — running it for real needs the actual ms_office_365_proplus target this check assesses.

# OVAL Definition: oval:mil.disa.stig.office365:def:223287
$compliant = $true
if (-not (Get-CimInstance -ClassName Win32_Product -Filter "Name like 'Microsoft Office 16.0%'")) {exit 1}
$regPath = "HKLM:\SOFTWARE\Policies\Microsoft\Office\16.0\common\toolbars"
if (-not (Test-Path $regPath)) {exit 0}
$apps = @("Access", "Excel", "PowerPoint", "Outlook", "Publisher", "Project", "Visio", "InfoPath")
foreach ($app in $apps) {
    $regKey = "$regPath\$app"
    if (-not (Test-Path $regKey)) {continue}
    if (-not (Get-ItemProperty -Path $regKey -Name "noextensibilitycustomizationfromdocument" -ErrorAction SilentlyContinue).noextensibilitycustomizationfromdocument -eq 1) {
        $compliant = $false
        break
    }
}
if ($compliant) {Write-Output "PASS"; exit 0} else {Write-Output "FAIL"; exit 1}

Remediation

Set the policy value for User Configuration >> Administrative Templates >> Microsoft Office 2016 >> Global Options >> Customize >> Disable UI extending from documents and templates to Enabled: Disallow in Word; Excel; PowerPoint; Access; Outlook; Publisher; Project; Visio; InfoPath.