Cis Azure Compute 15.3

Ensure local authentication methods for accounts are disabled

Description

This recommendation disables local authentication and ensures that a centralized identity provider is used.

Rationale

Identity and Authentication silos with stale or persistent keys and tokens can increase vulnerability and risk by preventing detection mechanisms from capturing anomalous activity and may not produce an auditable trail of evidence that can be used for pattern detection and forensic investigation. Centralized Identity providers such as Microsoft Entra ID are strongly preferred for all identity, authentication, authorization, and accountability (IAAA) systems and activities.

Impact

This control does not have an explicitly stated impact section. Disabling local authentication may affect existing automation or scripts that rely on Shared Key or Task Authentication Token methods.

Audit Procedure

Using Azure Portal

1. Login to Azure portal https://portal.azure.com
2. Navigate to Batch Accounts

For each Batch Account shown:

1. Click the Batch Account name
2. Under the Settings section, click on Authentication modes
3. In the main window, click the Authentication Mode drop-down list, and review which options are checked.

Expected Output: Only Microsoft Entra ID should be checked.

Using Azure CLI

Check Local Authentication Status for Batch Accounts:

az batch account list \
--query "[].{name:name, resourceGroup:resourceGroup, authModes:allowedAuthenticationModes}"

Expected Output:

• SHOULD contain "AAD" (Microsoft Entra ID)
• Should NOT contain "SharedKey" or other entries

Using Azure PowerShell

List Authentication Methods for All Batch Accounts using script:

Get-AzBatchAccount | ForEach-Object
{
    $authModes = (Get-AzBatchAccount -Name $_.AccountName -ResourceGroupName $_.ResourceGroupName).AllowedAuthenticationModes
    [PSCustomObject]@{
        AccountName = $_.AccountName
        ResourceGroup = $_.ResourceGroupName
        AuthenticationModes = $authModes -join ", "
    }
}

Expected Result

Only Microsoft Entra ID (AAD) should be listed as an allowed authentication mode. SharedKey and Task Authentication Token should not be enabled.

Remediation

Using Azure Portal

1. Login to Azure portal https://portal.azure.com
2. Navigate to Batch Accounts

For each Batch Account shown:

1. Click the Batch Account name
2. Under the Settings section, click on Authentication modes
3. In the main window, click the Authentication Mode drop-down list
4. Check the box for Microsoft Entra ID (or other centralized IdP)
5. (If checked) Uncheck the box for Shared Key
6. (If checked) Uncheck the box for Task Authentication Token
7. Click Save

Default Value

Local authentication methods are enabled by default.

References

1. https://learn.microsoft.com/en-us/azure/batch/security-best-practices#batch-account-authentication

Profile

Level 1 | Automated