Azure Firewall Created, Modified, or Deleted via Activity Log
Alerts on Azure Firewall write or delete events in Azure Activity Logs, signaling potential defense impairment.
- Product
- azure
- Service
- activitylogs
- Author
- Austin Songer @austinsonger (SigmaHQ), DRL 1.1
- Published
- 2021-08-08
- Updated
- 2026-07-31
ATT&CK techniques
Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact
What it detects
This rule flags activity log events where an Azure Firewall resource is written or deleted. Adversaries can impair defenses by changing firewall rules or removing the firewall entirely, so these actions warrant investigation. Detection relies on Azure Activity Logs operationName values for MICROSOFT.NETWORK/AZUREFIREWALLS/WRITE and MICROSOFT.NETWORK/AZUREFIREWALLS/DELETE, which indicate firewall configuration changes or deletion.
Reporting behind it
Changelog
v5- v5Candidate ingested via manual entry.2026-07-31
- v4Candidate ingested via manual entry.2026-07-31
- v3Candidate ingested via manual entry.2026-07-31
- v2Candidate ingested via manual entry.2026-07-31
- v1No changelog recorded for this version.2026-07-30
Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.
title: Azure Firewall Created, Modified, or Deleted via Activity Log
id: 348c9da1-06a5-4024-ad91-655ad81cc9bc
status: test
description: This rule flags activity log events where an Azure Firewall resource is written or deleted. Adversaries can impair defenses by changing firewall rules or removing the firewall entirely, so these actions warrant investigation. Detection relies on Azure Activity Logs operationName values for MICROSOFT.NETWORK/AZUREFIREWALLS/WRITE and MICROSOFT.NETWORK/AZUREFIREWALLS/DELETE, which indicate firewall configuration changes or deletion.
references:
- https://learn.microsoft.com/en-us/azure/role-based-access-control/resource-provider-operations
- https://github.com/SigmaHQ/sigma/blob/master/rules/cloud/azure/activity_logs/azure_firewall_modified_or_deleted.yml
author: Austin Songer @austinsonger, Huntrule Team
date: 2021-08-08
modified: 2022-08-23
tags:
- attack.impact
- attack.defense-impairment
- attack.t1686.001
logsource:
product: azure
service: activitylogs
detection:
selection:
operationName:
- MICROSOFT.NETWORK/AZUREFIREWALLS/WRITE
- MICROSOFT.NETWORK/AZUREFIREWALLS/DELETE
condition: selection
falsepositives:
- Firewall being modified or 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.
- Firewall modified or deleted 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: 512cf937-ea9b-4332-939c-4c2c94baadcd
type: derived