Detection: Kubernetes Azure scan fingerprint

DEPRECATED DETECTION

This detection has been marked as deprecated by the Splunk Threat Research team. This means that it will no longer be maintained or supported. If you have any questions or concerns, please reach out to us at research@splunk.com.

Updated Date: 2024-10-17 ID: c5e5bd5c-1013-4841-8b23-e7b3253c840a Author: Rod Soto, Splunk Type: Hunting Product: Splunk Enterprise Security

Description

This search provides information of unauthenticated requests via source IP user agent, request URI and response status data against Kubernetes cluster in Azure

Search

1`kubernetes_azure` category=kube-audit 
2| spath input=properties.log 
3| search responseStatus.code=401 
4| table  sourceIPs{} userAgent verb requestURI responseStatus.reason 
5|`kubernetes_azure_scan_fingerprint_filter`

Data Source

No data sources specified for this detection.

Macros Used

Name	Value
kubernetes_azure	`sourcetype=mscs:storage:blob:json`
kubernetes_azure_scan_fingerprint_filter	`search *`

kubernetes_azure_scan_fingerprint_filter is an empty macro by default. It allows the user to filter out any results (false positives) without editing the SPL.

Annotations

- MITRE ATT&CK

+ Kill Chain Phases

+ NIST

+ CIS

- Threat Actors

ID	Technique	Tactic
T1526	Cloud Service Discovery	Discovery

KillChainPhase.EXPLOITAITON

NistCategory.DE_AE

Cis18Value.CIS_10

Default Configuration

This detection is configured by default in Splunk Enterprise Security to run with the following settings:

Setting	Value
Disabled	true
Cron Schedule	`0 * * * *`
Earliest Time	`-70m@m`
Latest Time	`-10m@m`
Schedule Window	`auto`
Creates Risk Event	False

This configuration file applies to all detections of type hunting.

Implementation

You must install the Add-on for Microsoft Cloud Services and Configure Kube-Audit data diagnostics

Known False Positives

Not all unauthenticated requests are malicious, but source IPs, userAgent, verb, request URI and response status will provide context.

Associated Analytic Story

Kubernetes Scanning Activity

Risk Based Analytics (RBA)

Risk Message	Risk Score	Impact	Confidence
tbd	25	50	50

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

Detection Testing

Test Type	Status	Dataset	Source	Sourcetype
Validation	Not Applicable	N/A	N/A	N/A
Unit	❌ Failing	N/A	`N/A`	`N/A`
Integration	❌ Failing	N/A	`N/A`	`N/A`

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: GitHub | Version: 3