CIS.M365.5.1.4.6: Ensure users are restricted from recovering BitLocker keys


ID	`CIS.M365.5.1.4.6`
Severity	Medium
Suite	CIS Microsoft 365 Foundations Benchmark
Product	Entra ID
Feature	Device identity
Security area	Access control
Resource type	Tenant
User impact of fixing	Low
Effort to fix	Low
Benchmark	CIS Microsoft 365 Foundations Benchmark 7.0.0, `5.1.4.6` (L2, E3 Level 2, E5 Level 2)
Framework controls	`cis-m365:5.1.4.6` `nist-800-53-r5:AC-6(10)` Least Privilege \| Prohibit Non-privileged Users from Executing Privileged Functions `nist-800-53-r5:SC-28(3)` Protection of Information at Rest \| Cryptographic Keys
MITRE ATT&CK	T1552
Reads from	Microsoft Graph

What this checks and how to fix it

5.1.4.6 (L2) Ensure users are restricted from recovering BitLocker keys

This setting determines if users can self-service recover their BitLocker key(s). Restricting non-admin users from being able to see the BitLocker key(s) for their owned devices is the recommended state.

Rationale

Restricting user access to the self-service BitLocker recovery key portal helps mitigate the risk of recovery key exposure in the event of a compromised user account. If an attacker gains access to both the user’s credentials and the physical device, they could potentially retrieve the recovery key and decrypt sensitive data. The recovery key itself is also considered sensitive information.

Impact

Users will no longer be able to retrieve their own BitLocker recovery key(s) from the My Account portal or the Microsoft Entra admin center. They’ll need to contact a Cloud Device Administrator, Helpdesk Administrator, Intune Administrator, Security Administrator, or Security Reader to recover the key, which increases the support burden during device recovery scenarios.

Remediation action

Navigate to Microsoft 365 Entra admin center.
Click to expand Entra ID and select Devices > Device settings.
Set Restrict non-admin users from recovering the BitLocker key(s) for their owned devices to Yes.
Click the Save option at the top of the window.

Alternatively, use Microsoft Graph PowerShell:

Connect-MgGraph -Scopes Policy.ReadWrite.Authorization
$params = @{
 defaultUserRolePermissions = @{
  allowedToReadBitlockerKeysForOwnedDevice = $false
 }
}
Invoke-MgGraphRequest -Method PATCH -Uri "https://graph.microsoft.com/v1.0/policies/authorizationPolicy" -Body $params

Mito check, based on CIS Microsoft 365 Foundations Benchmark. Author: BakkerJan. Open-source licences.

Open-source licences. CIS Benchmark material © Center for Internet Security, Inc.; CISA SCuBA baselines are public domain (CC0).