Cis Azure Foundations 6.1.1.1

Ensure that a 'Diagnostic Setting' exists for Subscription Activity Logs

Description

Enable Diagnostic settings for exporting activity logs. Diagnostic settings are available for each individual resource within a subscription. Settings should be configured for all appropriate resources for your environment.

Rationale

A diagnostic setting controls how a diagnostic log is exported. By default, logs are retained only for 90 days. Diagnostic settings should be defined so that logs can be exported and stored for a longer duration to analyze security activities within an Azure subscription.

Impact

None identified.

Audit Procedure

Using Azure Portal

To identify Diagnostic Settings on a subscription:

1. Go to Monitor.
2. Click Activity Log.
3. Click Export Activity Logs.
4. Select a Subscription.
5. Ensure a Diagnostic setting exists for the selected Subscription.

To identify Diagnostic Settings on specific resources:

1. Go to Monitoring.
2. Click Diagnostic settings.
3. Ensure a Diagnostic setting exists for all appropriate resources.

Using Azure CLI

To identify Diagnostic Settings on a subscription:

az monitor diagnostic-settings subscription list --subscription <subscription-id>

To identify Diagnostic Settings on a resource:

az monitor diagnostic-settings list --resource <resource-id>

Using PowerShell

To identify Diagnostic Settings on a Subscription:

Get-AzSubscriptionDiagnosticSetting -SubscriptionId <subscription-id>

To identify Diagnostic Settings on a specific resource:

Get-AzDiagnosticSetting -ResourceId <resource-id>

Expected Result

At least one Diagnostic Setting should exist for each subscription, exporting activity logs to a destination such as Log Analytics workspace, Storage Account, or Event Hub.

Remediation

Remediate from Azure Portal

To enable Diagnostic Settings on a Subscription:

1. Go to Monitor.
2. Click on Activity log.
3. Click on Export Activity Logs.
4. Click + Add diagnostic setting.
5. Enter a Diagnostic setting name.
6. Select Categories for the diagnostic setting.
7. Select the appropriate Destination details (Log Analytics, Storage Account, Event Hub, or Partner solution).
8. Click Save.

Remediate from Azure CLI

az monitor diagnostic-settings subscription create --subscription <subscription id> --name <diagnostic settings name> --location <location> <[--event-hub <event hub ID> --event-hub-auth-rule <event hub auth rule ID>] [--storage-account <storage account ID>] [--workspace <log analytics workspace ID>]> --logs "<JSON encoded categories>" (e.g. [{category:Security,enabled:true},{category:Administrative,enabled:true},{category:Alert,enabled:true},{category:Policy,enabled:true}])

Remediate from PowerShell

$logCategories = @();
$logCategories += New-AzDiagnosticSettingSubscriptionLogSettingsObject -Category Administrative -Enabled $true
$logCategories += New-AzDiagnosticSettingSubscriptionLogSettingsObject -Category Security -Enabled $true
$logCategories += New-AzDiagnosticSettingSubscriptionLogSettingsObject -Category ServiceHealth -Enabled $true
$logCategories += New-AzDiagnosticSettingSubscriptionLogSettingsObject -Category Alert -Enabled $true
$logCategories += New-AzDiagnosticSettingSubscriptionLogSettingsObject -Category Recommendation -Enabled $true
$logCategories += New-AzDiagnosticSettingSubscriptionLogSettingsObject -Category Policy -Enabled $true
$logCategories += New-AzDiagnosticSettingSubscriptionLogSettingsObject -Category Autoscale -Enabled $true
$logCategories += New-AzDiagnosticSettingSubscriptionLogSettingsObject -Category ResourceHealth -Enabled $true

New-AzSubscriptionDiagnosticSetting -SubscriptionId <subscription ID> -Name <Diagnostic settings name> <[-EventHubAuthorizationRule <event hub auth rule ID> -EventHubName <event hub name>] [-StorageAccountId <storage account ID>] [-WorkSpaceId <log analytics workspace ID>] [-MarketplacePartner ID <full ARM Marketplace resource ID>]> -Log $logCategories

Default Value

No Diagnostic Settings are configured by default.

References

1. https://learn.microsoft.com/en-us/azure/azure-monitor/essentials/diagnostic-settings
2. https://learn.microsoft.com/en-us/azure/azure-monitor/essentials/resource-manager-diagnostic-settings
3. https://learn.microsoft.com/en-us/security/benchmark/azure/mcsb-logging-threat-detection#lt-3-enable-logging-for-security-investigation
4. https://learn.microsoft.com/en-us/cli/azure/monitor/diagnostic-settings?view=azure-cli-latest
5. https://learn.microsoft.com/en-us/powershell/module/az.monitor/new-azsubscriptiondiagnosticsetting?view=azps-13.4.0

CIS Controls

MITRE ATT&CK Mappings

Profile

Level 1 | Automated