Azure Activity Logs: Kubernetes Network Policy Write/Delete Changes

Alerts on Azure Activity Log events that modify or remove Kubernetes network policies for connected clusters.

FreeReviewedSigma · Medium · v5
Product
azure
Service
activitylogs
Author
Austin Songer @austinsonger (SigmaHQ), DRL 1.1
Published
2021-08-07
Updated
2026-07-31
title: "Azure Activity Logs: Kubernetes Network Policy Write/Delete Changes"
id: 6c95d129-666f-43b6-b90e-90e3e5f0719f
status: test
description: This rule identifies Azure Kubernetes network policy modifications or deletions by matching Activity Log operation names for network policy write and delete actions. Attackers may change network policies to disrupt segmentation or enable unintended pod-to-pod or pod-to-service communication. It relies on Azure Activity Log telemetry capturing the operationName and the identity associated with the change.
references:
  - https://learn.microsoft.com/en-us/azure/role-based-access-control/resource-provider-operations#microsoftkubernetes
  - https://www.microsoft.com/security/blog/2021/03/23/secure-containerized-environments-with-updated-threat-matrix-for-kubernetes/
  - https://www.microsoft.com/security/blog/2020/04/02/attack-matrix-kubernetes/
  - https://medium.com/mitre-engenuity/att-ck-for-containers-now-available-4c2359654bf1
  - https://github.com/SigmaHQ/sigma/blob/master/rules/cloud/azure/activity_logs/azure_kubernetes_network_policy_change.yml
author: Austin Songer @austinsonger, Huntrule Team
date: 2021-08-07
modified: 2022-08-23
tags:
  - attack.impact
  - attack.credential-access
  - attack.t1485
  - attack.t1496
  - attack.t1489
logsource:
  product: azure
  service: activitylogs
detection:
  selection:
    operationName:
      - MICROSOFT.KUBERNETES/CONNECTEDCLUSTERS/NETWORKING.K8S.IO/NETWORKPOLICIES/WRITE
      - MICROSOFT.KUBERNETES/CONNECTEDCLUSTERS/NETWORKING.K8S.IO/NETWORKPOLICIES/DELETE
      - MICROSOFT.KUBERNETES/CONNECTEDCLUSTERS/EXTENSIONS/NETWORKPOLICIES/WRITE
      - MICROSOFT.KUBERNETES/CONNECTEDCLUSTERS/EXTENSIONS/NETWORKPOLICIES/DELETE
  condition: selection
falsepositives:
  - Network Policy being 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.
  - Network Policy being modified and 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: 08d6ac24-c927-4469-b3b7-2e422d6e3c43
    type: derived