Sigma Rule Library

Azure Kubernetes CronJob

Identifies when a Azure Kubernetes CronJob runs in Azure Cloud. Kubernetes Job is a controller that creates one or more pods and ensures that a specified number of them successfully terminate. Kubernetes Job can be used to run containers that perform finite tasks for batch jobs. Kubernetes CronJob is used to schedule Jobs. An Adversary may use Kubernetes CronJob for scheduling execution of malicious code that would run as a container in the cluster.

View on GitHubOpen raw file

Detection logic

selection

operationName|startswith:
  - MICROSOFT.KUBERNETES/CONNECTEDCLUSTERS/BATCH
  - MICROSOFT.CONTAINERSERVICE/MANAGEDCLUSTERS/BATCH
operationName|endswith:
  - /CRONJOBS/WRITE
  - /JOBS/WRITE

Condition

selection

Raw YAML

title: Azure Kubernetes CronJob
id: 1c71e254-6655-42c1-b2d6-5e4718d7fc0a
status: test
description: |
  Identifies when a Azure Kubernetes CronJob runs in Azure Cloud. Kubernetes Job is a controller that creates one or more pods and ensures that a specified number of them successfully terminate.
  Kubernetes Job can be used to run containers that perform finite tasks for batch jobs. Kubernetes CronJob is used to schedule Jobs.
  An Adversary may use Kubernetes CronJob for scheduling execution of malicious code that would run as a container in the cluster.
references:
    - https://learn.microsoft.com/en-us/azure/role-based-access-control/resource-provider-operations#microsoftkubernetes
    - https://kubernetes.io/docs/concepts/workloads/controllers/cron-jobs/
    - https://kubernetes.io/docs/concepts/workloads/controllers/job/
    - https://www.microsoft.com/security/blog/2020/04/02/attack-matrix-kubernetes/
author: Austin Songer @austinsonger
date: 2021-11-22
modified: 2022-12-18
tags:
    - attack.persistence
    - attack.t1053.003
    - attack.privilege-escalation
    - attack.execution
logsource:
    product: azure
    service: activitylogs
detection:
    selection:
        operationName|startswith:
            - 'MICROSOFT.KUBERNETES/CONNECTEDCLUSTERS/BATCH'
            - 'MICROSOFT.CONTAINERSERVICE/MANAGEDCLUSTERS/BATCH'
        operationName|endswith:
            - '/CRONJOBS/WRITE'
            - '/JOBS/WRITE'
    condition: selection
falsepositives:
    - Azure Kubernetes CronJob/Job may be done by a system administrator.
    - If known behavior is causing false positives, it can be exempted from the rule.
level: medium

False positives

  • Azure Kubernetes CronJob/Job may be done by a system administrator.
  • If known behavior is causing false positives, it can be exempted from the rule.

References

Similar rules