Azure Storage Account Deleted

AnalysisType: rule
Filename: azure_storage_account_deleted.py
RuleID: "Azure.MonitorActivity.StorageAccount.Deleted"
DisplayName: "Azure Storage Account Deleted"
Enabled: true
LogTypes:
  - Azure.MonitorActivity
Severity: High
Description: >
  Detects when an Azure storage account is deleted.
  Storage account deletion is a destructive operation that may indicate ransomware activity or malicious data destruction.
Reports:
  MITRE ATT&CK:
    - TA0040:T1485 # Impact: Data Destruction
    - TA0040:T1490 # Impact: Inhibit System Recovery
Tags:
  - Impact
  - Data Destruction
  - Inhibit System Recovery
  - Ransomware
Runbook: |
  1. Query Azure Monitor Activity logs for all storage account operations by the callerIpAddress in the 24 hours before this alert to establish if this is part of a larger attack pattern
  2. Check if the source IP is associated with known cloud providers, VPN services, or corporate network ranges using threat intelligence
  3. Search for other Azure resource deletions or destructive operations from the same user or IP in the past 7 days to assess the scope of potential data destruction
Reference: https://www.trendmicro.com/cloudoneconformity/knowledge-base/azure/ActivityLog/delete-storage-account-alert.html
SummaryAttributes:
  - resourceId
  - callerIpAddress
  - correlationId
Tests:
  - Name: Storage Account Deleted
    ExpectedResult: true
    Log:
      {
        "time": "2024-12-17T10:30:00.0000000Z",
        "resourceId": "/subscriptions/12345678-1234-1234-1234-123456789abc/resourceGroups/myresourcegroup/providers/Microsoft.Storage/storageAccounts/mystorageaccount",
        "operationName": "Microsoft.Storage/storageAccounts/delete",
        "operationVersion": "2021-04-01",
        "category": "Administrative",
        "resultType": "Success",
        "resultSignature": "200",
        "durationMs": 1523,
        "callerIpAddress": "1.1.1.1",
        "correlationId": "a1b2c3d4-e5f6-7890-abcd-ef1234567890",
        "level": "Informational",
        "location": "eastus",
        "tenantId": "87654321-4321-4321-4321-111111111111"
      }
  - Name: Case Insensitive Match
    ExpectedResult: true
    Log:
      {
        "time": "2024-12-17T11:45:00.0000000Z",
        "resourceId": "/subscriptions/12345678-1234-1234-1234-123456789abc/resourceGroups/prod-rg/providers/Microsoft.Storage/storageAccounts/prodstorage",
        "operationName": "microsoft.storage/storageaccounts/delete",
        "operationVersion": "2021-04-01",
        "category": "Administrative",
        "resultType": "Succeeded",
        "callerIpAddress": "1.2.3.4",
        "correlationId": "f9e8d7c6-b5a4-3210-9876-fedcba098765",
        "tenantId": "87654321-4321-4321-4321-111111111111"
      }
  - Name: Different Operation
    ExpectedResult: false
    Log:
      {
        "time": "2024-12-17T13:30:00.0000000Z",
        "resourceId": "/subscriptions/12345678-1234-1234-1234-123456789abc/resourceGroups/myresourcegroup/providers/Microsoft.Storage/storageAccounts/mystorageaccount",
        "operationName": "Microsoft.Storage/storageAccounts/write",
        "operationVersion": "2021-04-01",
        "category": "Administrative",
        "resultType": "Success",
        "callerIpAddress": "3.3.3.3",
        "correlationId": "d4e5f6a7-b8c9-0123-def0-444444444444",
        "tenantId": "87654321-4321-4321-4321-111111111111"
      }