Make hidden markup visible in PowerPoint - prevents accidental information disclosure via hidden comments/annotations.
Aanbeveling
IMPLEMENT
Risico zonder
Low
Risk Score
4/10
Implementatie
4u (tech: 1u)
Van toepassing op:
β Microsoft PowerPoint
Hidden markup = data leakage: PowerPoint markup: Comments, reviewer annotations, tracked changes, hidden slides, speaker notes, Hidden content: Visible to author (during editing) BUT hidden in presentation mode, Data leakage scenario: Confidential comment 'DO NOT share pricing with customer' β hidden during presentation BUT visible if recipient opens file in edit mode. Attack: External recipient opens .pptx β sees hidden comments β sensitive info leaked. Make visible: Forces authors to SEE hidden markup (awareness) β remove before sharing.
User training: Remove hidden markup before sharing
Implementatie
Intune Settings Catalog: PowerPoint\Security β Make hidden markup visible: Enabled. Training: Users run Document Inspector (File β Info β Check for Issues β Inspect Document) before external sharing.
Compliance
BIO 08.02 (Information classification), ISO 27001 A.8.2.3 (Information labeling).
Monitoring
Gebruik PowerShell-script make-hidden-markup-visible.ps1 (functie Invoke-Monitoring) β Controleren.
Remediatie
Gebruik PowerShell-script make-hidden-markup-visible.ps1 (functie Invoke-Remediation) β Herstellen.
Compliance & Frameworks
BIO: 08.02.02 -
ISO 27001:2022: A.8.2.3 -
Automation
Gebruik het onderstaande PowerShell script om deze security control te monitoren en te implementeren. Het script bevat functies voor zowel monitoring (-Monitoring) als remediation (-Remediation).
PowerShell
<#
.SYNOPSIS
Maakt verborgen markup zichtbaar in PowerPoint
.DESCRIPTION
Dit script implementeert CIS control O365-PT-000001 voor het zichtbaar maken van verborgen
markup in Microsoft PowerPoint. Dit voorkomt dat gevoelige informatie verborgen blijft in
presentaties die worden gedeeld.
.REQUIREMENTS
- PowerShell 5.1 of hoger
- Lokale administrator rechten voor registry wijzigingen
- Microsoft PowerPoint geΓ―nstalleerd
.PARAMETER Monitoring
Controleert de huidige compliance status
.PARAMETER Remediation
Past de aanbevolen configuratie toe
.PARAMETER Revert
Herstelt de originele configuratie
.PARAMETER WhatIf
Toont wat er zou gebeuren zonder wijzigingen door te voeren
.EXAMPLE
.\make-hidden-markup-visible.ps1 -Monitoring
Controleert of verborgen markup zichtbaar wordt gemaakt
.EXAMPLE
.\make-hidden-markup-visible.ps1 -Remediation
Maakt verborgen markup zichtbaar
.NOTES
Registry pad: HKCU:\Software\Policies\Microsoft\Office\16.0\POWERPOINT\Security
Waarde: makehiddenmarkupvisible = 1
CIS Control: O365-PT-000001
DISA STIG: Microsoft Office 365 ProPlus v3r3
#>#Requires -Version 5.1param(
[switch]$Monitoring,
[switch]$Remediation,
[switch]$Revert,
[switch]$WhatIf
)
# Globale variabelen$RegistryPath = "HKCU:\Software\Policies\Microsoft\Office\16.0\POWERPOINT\Security"
$ValueName = "makehiddenmarkupvisible"
$ExpectedValue = 1$ControlID = "O365-PT-000001"
functionTest-Compliance {
try {
if (-not (Test-Path$RegistryPath)) {
return$false
}
$currentValue = Get-ItemProperty -Path $RegistryPath -Name $ValueName -ErrorAction SilentlyContinue
return ($currentValue -and $currentValue.$ValueName -eq $ExpectedValue)
}
catch {
return$false
}
}
function Invoke-Monitoring {
Write-Host "Monitoring ${ControlID}: Verborgen markup zichtbaar maken" -ForegroundColor Green
try {
if (-not (Test-Path$RegistryPath)) {
Write-Host "β Registry pad bestaat niet: $RegistryPath" -ForegroundColor Red
return$false
}
$currentValue = Get-ItemProperty -Path $RegistryPath -Name $ValueName -ErrorAction SilentlyContinue
if ($currentValue -and $currentValue.$ValueName -eq $ExpectedValue) {
Write-Host "β Control compliant: ${ValueName} = $ExpectedValue" -ForegroundColor Green
return$true
}
else {
$actualValue = if ($currentValue) { $currentValue.$ValueName } else { "Not Set" }
Write-Host "β Control non-compliant: ${ValueName} = $actualValue (Expected: $ExpectedValue)" -ForegroundColor Red
return$false
}
}
catch {
Write-Host "β Fout bij controleren registry instelling: $($_.Exception.Message)" -ForegroundColor Red
return$false
}
}
function Invoke-Remediation {
Write-Host "Remediating ${ControlID}: Verborgen markup zichtbaar maken" -ForegroundColor Yellow
try {
if ($WhatIf) {
Write-Host "WhatIf: Zou registry waarde instellen: ${ValueName} = $ExpectedValue" -ForegroundColor Cyan
return$true
}
if (-not (Test-Path$RegistryPath)) {
Write-Host "Registry pad aanmaken: $RegistryPath" -ForegroundColor Yellow
New-Item -Path $RegistryPath -Force | Out-Null
}
Set-ItemProperty -Path $RegistryPath -Name $ValueName -Value $ExpectedValue -Type DWord -Force
Write-Host "β Registry waarde succesvol ingesteld: ${ValueName} = $ExpectedValue" -ForegroundColor Green
Start-Sleep -Seconds 1return Invoke-Monitoring
}
catch {
Write-Host "β Fout bij configureren registry instelling: $($_.Exception.Message)" -ForegroundColor Red
return$false
}
}
function Invoke-Revert {
Write-Host "Reverting ${ControlID}: Verborgen markup instelling herstellen" -ForegroundColor Yellow
try {
if ($WhatIf) {
Write-Host "WhatIf: Zou registry waarde verwijderen: ${ValueName}" -ForegroundColor Cyan
return$true
}
if (Test-Path$RegistryPath) {
Remove-ItemProperty -Path $RegistryPath -Name $ValueName -ErrorAction SilentlyContinue
Write-Host "β Registry waarde verwijderd: ${ValueName}" -ForegroundColor Green
}
return$true
}
catch {
Write-Host "β Fout bij herstellen registry instelling: $($_.Exception.Message)" -ForegroundColor Red
return$false
}
}
# Hoofd uitvoeringtry {
if ($Monitoring) {
$result = Invoke-Monitoring
exit $(if ($result) { 0 } else { 1 })
}
elseif ($Remediation) {
$result = Invoke-Remediation
exit $(if ($result) { 0 } else { 1 })
}
elseif ($Revert) {
$result = Invoke-Revert
exit $(if ($result) { 0 } else { 1 })
}
else {
Write-Host "Gebruik: .\network-trusted-locations-disabled.ps1 [-Monitoring] [-Remediation] [-Revert] [-WhatIf]" -ForegroundColor Yellow
Write-Host " -Monitoring: Controleer huidige compliance status" -ForegroundColor White
Write-Host " -Remediation: Pas aanbevolen configuratie toe" -ForegroundColor White
Write-Host " -Revert: Herstel originele configuratie" -ForegroundColor White
Write-Host " -WhatIf: Toon wat er zou gebeuren" -ForegroundColor White
}
}
catch {
Write-Host "β Onverwachte fout: $($_.Exception.Message)" -ForegroundColor Red
exit 1
}
Risico zonder implementatie
Risico zonder implementatie
Low: Low: Hidden markup = accidental confidential info disclosure.
Management Samenvatting
Make PowerPoint hidden markup visible. Prevent data leakage via comments. Train users: Document Inspector. Implementatie: 1-4 uur.