Azure DNS Zone Modified or Deleted via Activity Logs

title: Azure DNS Zone Modified or Deleted via Activity Logs
id: 962a58a3-fbc1-4adc-a4ab-ddc71afc49cf
status: test
description: This rule flags Azure Activity Log events where the operation name indicates a DNS zone WRITE or DELETE action. Attackers may modify or remove DNS zones to disrupt name resolution or redirect traffic, making this high-impact behavior important to monitor. Detection relies on Azure Activity Logs fields that include operationName values starting with MICROSOFT.NETWORK/DNSZONES and ending with /WRITE or /DELETE.
references:
  - https://learn.microsoft.com/en-us/azure/role-based-access-control/resource-provider-operations#microsoftkubernetes
  - https://github.com/SigmaHQ/sigma/blob/master/rules/cloud/azure/activity_logs/azure_dns_zone_modified_or_deleted.yml
author: Austin Songer @austinsonger, Huntrule Team
date: 2021-08-08
modified: 2022-08-23
tags:
  - attack.impact
  - attack.t1565.001
logsource:
  product: azure
  service: activitylogs
detection:
  selection:
    operationName|startswith: MICROSOFT.NETWORK/DNSZONES
    operationName|endswith:
      - /WRITE
      - /DELETE
  condition: selection
falsepositives:
  - DNS zone modified and deleted may be performed by a system administrator. Verify whether the user identity, user agent, and/or hostname should be making changes in your environment.
  - DNS zone modification from unfamiliar users should be investigated. If known behavior is causing false positives, it can be exempted from the rule.
level: medium
license: DRL-1.1
related:
  - id: af6925b0-8826-47f1-9324-337507a0babd
    type: derived