Account should have a activity log alert configured for 'Delete Storage Accounts'

azure.activity_log

Description

Create an activity log alert for the Delete Storage Account event.

Rationale

By monitoring for storage accounts deletion events, you gain insight into storage account changes and may reduce the time it takes to detect suspicious activity.

Remediation

From the console

  1. Navigate to Monitor.
  2. Select Alerts.
  3. Click on New Alert Rule.
  4. Under Scope, click Select scope.
  5. Select the appropriate subscription under Filter by subscription.
  6. Select Storage Accounts under Filter by resource type.
  7. Select All for Filter by location.
  8. Click on the Include all future resources checkbox.
  9. Click Done.
  10. Under Condition, click Add Condition.
  11. Select Delete Storage Account signal.
  12. Click Done.
  13. Under Actions, select Add action groups and either complete the creation process, or select the appropriate action group.
  14. Under Alert rule details, enter Alert rule name and Description.
  15. Select appropriate resource group to save the alert to.
  16. Click on the Enable alert rule upon creation checkbox.
  17. Click Create alert rule.

From the command line

az account get-access-token --query "{subscription:subscription,accessToken:accessToken}" --out tsv | xargs -L1 bash -c 'curl -X PUT -H "Authorization: Bearer $1" -H "Content-Type: application/json" https://management.azure.com/subscriptions/$0/resourceGroups/<Resource_Group_ To_Create_Alert_In>/providers/microsoft.insights/activityLogAlerts/<Unique_Alert _Name>?api-version=2017-04-01 -d@"input.json"'

Where input.json contains the request body JSON data, as mentioned below.

{
  "location": "Global",
  "tags": {},
  "properties": {
    "scopes": [
      "/subscriptions/<Subscription_ID>"
    ],
    "enabled": true,
    "condition": {
      "allOf": [
        {
          "containsAny": null,
          "equals": "Administrative",
          "field": "category"
        },
        {
          "field": "operationName",
          "equals": "Microsoft.Storage/storageAccounts/delete"
        }
      ]
    },
    "actions": {
      "actionGroups": [
        {
          "actionGroupId": "/subscriptions/<Subscription_ID>/resourceGroups/<Resource_Group_For_Alert_Group>/providers/microsoft.insights/actionGroups/<Alert_Group>",
          "webhookProperties": null
        }
      ]
    },
  }
}

References

  1. https://azure.microsoft.com/en-us/updates/classic-alerting-monitoring-retirement
  2. https://docs.microsoft.com/en-in/azure/azure-monitor/platform/alerts-activity-log
  3. https://docs.microsoft.com/en-in/rest/api/monitor/activitylogalerts/createorupdate
  4. https://docs.microsoft.com/en-in/rest/api/monitor/activitylogalerts/listbysubscriptionid
  5. https://docs.microsoft.com/en-us/azure/security/benchmarks/security-controls-v2-logging-threat-detection#lt-4-enable-logging-for-azure-resources

CIS Controls

Version 7, 6.3 - Enable Detailed Logging: Enable system logging to include detailed information such as an event source, date, user, timestamp, source addresses, destination addresses, and other useful elements.