Kubernetes AWS detect suspicious kubectl calls


Description

The following analytic detects anonymous and unauthenticated requests to a Kubernetes cluster. It identifies this behavior by monitoring API calls from users who have not provided any token or password in their request, using data from kube_audit logs. This activity is significant for a SOC as it indicates a severe misconfiguration, allowing unfettered access to the cluster with no traceability. If confirmed malicious, an attacker could gain access to sensitive data or control over the cluster, posing a substantial security risk.

Query · spl

`kube_audit` user.username="system:anonymous" user.groups{} IN ("system:unauthenticated")
  | fillnull
  | stats count
    BY objectRef.name objectRef.namespace objectRef.resource
       requestReceivedTimestamp requestURI responseStatus.code
       sourceIPs{} stage user.groups{}
       user.uid user.username userAgent
       verb
  | rename sourceIPs{} as src_ip, user.username as user
  | `kubernetes_aws_detect_suspicious_kubectl_calls_filter`

Implementation guide

The detection is based on data that originates from Kubernetes Audit logs. Ensure that audit logging is enabled in your Kubernetes cluster. Kubernetes audit logs provide a record of the requests made to the Kubernetes API server, which is crucial for monitoring and detecting suspicious activities. Configure the audit policy in Kubernetes to determine what kind of activities are logged. This is done by creating an Audit Policy and providing it to the API server. Use the Splunk OpenTelemetry Collector for Kubernetes to collect the logs. This doc will describe how to collect the audit log file https://github.com/signalfx/splunk-otel-collector-chart/blob/main/docs/migration-from-sck.md. When you want to use this detection with AWS EKS, you need to enable EKS control plane logging https://docs.aws.amazon.com/eks/latest/userguide/control-plane-logs.html. Then you can collect the logs from Cloudwatch using the AWS TA https://splunk.github.io/splunk-add-on-for-amazon-web-services/CloudWatchLogs/.

Known false positives

  • Kubectl calls are not malicious by nature. However source IP, verb and Object can reveal potential malicious activity, specially anonymous suspicious IPs and sensitive objects such as configmaps or secrets

Analyst notes

Known false positives: Kubectl calls are not malicious by nature. However source IP, verb and Object can reveal potential malicious activity, specially anonymous suspicious IPs and sensitive objects such as configmaps or secrets

Raw source Kubernetes AWS detect suspicious kubectl calls · SPL
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Published by splunk/security_content ↗, licensed under Apache 2.0 ↗. Reproduced here unmodified.
name: Kubernetes AWS detect suspicious kubectl calls
id: 042a3d32-8318-4763-9679-09db2644a8f2
version: 9
creation_date: '2020-06-23'
modification_date: '2026-05-13'
author: Rod Soto, Patrick Bareiss, Splunk
status: experimental
type: Anomaly
description: The following analytic detects anonymous and unauthenticated requests to a Kubernetes cluster. It identifies this behavior by monitoring API calls from users who have not provided any token or password in their request, using data from `kube_audit` logs. This activity is significant for a SOC as it indicates a severe misconfiguration, allowing unfettered access to the cluster with no traceability. If confirmed malicious, an attacker could gain access to sensitive data or control over the cluster, posing a substantial security risk.
data_source:
    - Kubernetes Audit
search: |-
    `kube_audit` user.username="system:anonymous" user.groups{} IN ("system:unauthenticated")
      | fillnull
      | stats count
        BY objectRef.name objectRef.namespace objectRef.resource
           requestReceivedTimestamp requestURI responseStatus.code
           sourceIPs{} stage user.groups{}
           user.uid user.username userAgent
           verb
      | rename sourceIPs{} as src_ip, user.username as user
      | `kubernetes_aws_detect_suspicious_kubectl_calls_filter`
how_to_implement: The detection is based on data that originates from Kubernetes Audit logs. Ensure that audit logging is enabled in your Kubernetes cluster. Kubernetes audit logs provide a record of the requests made to the Kubernetes API server, which is crucial for monitoring and detecting suspicious activities. Configure the audit policy in Kubernetes to determine what kind of activities are logged. This is done by creating an Audit Policy and providing it to the API server. Use the Splunk OpenTelemetry Collector for Kubernetes to collect the logs. This doc will describe how to collect the audit log file https://github.com/signalfx/splunk-otel-collector-chart/blob/main/docs/migration-from-sck.md. When you want to use this detection with AWS EKS, you need to enable EKS control plane logging https://docs.aws.amazon.com/eks/latest/userguide/control-plane-logs.html. Then you can collect the logs from Cloudwatch using the AWS TA https://splunk.github.io/splunk-add-on-for-amazon-web-services/CloudWatchLogs/.
known_false_positives: Kubectl calls are not malicious by nature. However source IP, verb and Object can reveal potential malicious activity, specially anonymous suspicious IPs and sensitive objects such as configmaps or secrets
references: []
intermediate_findings:
    entities:
        - field: user
          type: user
          score: 20
          message: Suspicious kubectl API calls from $user$
analytic_story:
    - Kubernetes Security
asset_type: Kubernetes
mitre_attack_id: []
product:
    - Splunk Enterprise
    - Splunk Enterprise Security
    - Splunk Cloud
category: cloud
security_domain: threat

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