TMA-CHROME-1.10
Ensure 'Disable Certificate Transparency enforcement for a list of Legacy Certificate Authorities' is set to 'Disabled'
Description
Google Chrome can disable the enforcing of Certificate Transparency requirements for a list of Legacy Certificate Authorities. If this setting is disabled, certificates not properly publicly disclosed as required by Certificate Transparency are untrusted. The recommended state for this setting is: Disabled (0) Rationale: Legacy Certificate Authorities shall follow the Certificate Transparency policy. The policy is Disabled when it is not present: the audit prints 'absent' when the list key HKLM\SOFTWARE\Policies\Google\Chrome\CertificateTransparencyEnforcementDisabledForLegacyCas is missing or empty, otherwise the configured entries.
How it is checked
Audit method: Windows registry
$l = @((Get-ItemProperty -Path 'Registry::HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Google\Chrome\CertificateTransparencyEnforcementDisabledForLegacyCas' -ErrorAction SilentlyContinue).PSObject.Properties | Where-Object { $_.Name -notlike 'PS*' } | ForEach-Object { "$($_.Value)" }); if ($l.Count -eq 0) { 'absent' } else { 'configured: ' + ($l -join ', ') }- Expected output
absent
How it is fixed
Fix method: Guidance or infrastructure patch
Configure through Group Policy: Computer Configuration\Policies\Administrative Templates\Google\Google Chrome\Disable Certificate Transparency enforcement for a list of Legacy Certificate Authorities = Disabled. Locally, remove the policy entries at HKLM\SOFTWARE\Policies\Google\Chrome\CertificateTransparencyEnforcementDisabledForLegacyCas after reviewing them.
Properties
- Operating systems
- Any
- Tags
- chromebrowsercis-l1
- Reference
- CIS Google Chrome Benchmark v3.0.0 - 1.10 Ensure 'Disable Certificate Transparency enforcement for a list of Legacy Certificate Authorities' is set to 'Disabled'
Check this host
Run this on a machine you are allowed to audit. The scan is read-only.
tmaegis scan --target chrome