:warning: THIS IS A EXPERIMENTAL DETECTION

This detection has been marked experimental by the Splunk Threat Research team. This means we have not been able to test, simulate, or build datasets for this detection. Use at your own risk. This analytic is NOT supported.

Try in Splunk Security Cloud

Description

The following analytic detects unauthenticated requests made against the Kubernetes Pods API, indicating potential unauthorized access attempts. It leverages the aws_cloudwatchlogs_eks data source, filtering for events where user.username is "system:anonymous", verb is "list", and objectRef.resource is "pods", with requestURI set to "/api/v1/pods". This activity is significant as it may signal attempts to access sensitive resources or execute unauthorized commands within the Kubernetes environment. If confirmed malicious, such access could lead to data compromise, unauthorized command execution, or lateral movement within the cluster.

  • Type: Hunting

  • Product: Splunk Enterprise, Splunk Enterprise Security, Splunk Cloud

  • Last Updated: 2024-05-29
  • Author: Rod Soto, Splunk
  • ID: dbfca1dd-b8e5-4ba4-be0e-e565e5d62002

Annotations

ATT&CK

ATT&CK

ID Technique Tactic
T1526 Cloud Service Discovery Discovery
Kill Chain Phase
  • Exploitation
NIST
  • DE.AE
CIS20
  • CIS 10
CVE 


1
2
3
4
5
6



`aws_cloudwatchlogs_eks` "user.username"="system:anonymous" verb=list objectRef.resource=pods requestURI="/api/v1/pods" 
| rename source as cluster_name sourceIPs{} as src_ip 
| stats count min(_time) as firstTime max(_time) as lastTime values(responseStatus.reason) values(responseStatus.code) values(userAgent) values(verb) values(requestURI) by src_ip cluster_name user.username user.groups{} 
| `security_content_ctime(lastTime)` 
| `security_content_ctime(firstTime)` 
| `amazon_eks_kubernetes_pod_scan_detection_filter`

Macros

The SPL above uses the following Macros:

:information_source: amazon_eks_kubernetes_pod_scan_detection_filter is a empty macro by default. It allows the user to filter out any results (false positives) without editing the SPL.

Required fields

List of fields required to use this analytic.

  • _time
  • user.username
  • verb
  • objectRef.resource
  • requestURI
  • source
  • sourceIPs{}
  • responseStatus.reason
  • responseStatus.code
  • userAgent
  • src_ip
  • user.groups{}

How To Implement

You must install the AWS App for Splunk (version 5.1.0 or later) and Splunk Add-on forAWS (version 4.4.0 or later), then configure your AWS CloudWatch EKS Logs.Please also customize the kubernetes_pods_aws_scan_fingerprint_detection macro to filter out the false positives.

Known False Positives

Not all unauthenticated requests are malicious, but frequency, UA and source IPs and direct request to API provide context.

Associated Analytic Story

RBA

Risk Score Impact Confidence Message
25.0 50 50 tbd

:information_source: The Risk Score is calculated by the following formula: Risk Score = (Impact * Confidence/100). Initial Confidence and Impact is set by the analytic author.

Reference

Test Dataset

Replay any dataset to Splunk Enterprise by using our replay.py tool or the UI. Alternatively you can replay a dataset into a Splunk Attack Range

source | version: 2