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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.

MITRE ATT&CK

T1053.003

persistenceprivilege-escalationexecution

Detection Query

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

Author

Austin Songer @austinsonger

Created

2021-11-22

Data Sources

azureactivitylogs

Platforms

azure

References

Tags

attack.persistenceattack.t1053.003attack.privilege-escalationattack.execution

Raw Content

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