Kubernetes Potential Enumeration Activity — Sigma Rule

Rule metadata and linked tags

Author: uniqu3-us3r. Source status: experimental; severity: medium. Source dates: 2026-04-28 / not supplied.

{
  "product": "kubernetes",
  "service": "audit"
}

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: 655efe6ff52c0853eb1640aa2de0867e37d8a67746e48f1f31d687b1b3025ffe

Detection logic

Original source YAML. Source-tag agreement is not proof of complete semantic coverage. This rule has not been compiled for a SIEM backend or validated against live telemetry here.

title: Kubernetes Potential Enumeration Activity
id: 597a7e84-187d-458b-9e4f-2f5a0e676711
status: experimental
description: |
    Detects potential Kubernetes enumeration or attack activity via the audit log.
    This includes the execution of common shells, utilities, or specialized tools like 'Rakkess' (access_matrix) and 'TruffleHog' via Kubernetes API requests.
    Attackers use these methods to perform reconnaissance (enumeration), secret harvesting, or execute code (exec) within a cluster.
references:
    - https://www.nccgroup.com/research/detection-engineering-for-kubernetes-clusters/
    - https://github.com/trufflesecurity/trufflehog
    - https://github.com/corneliusweig/rakkess
author: uniqu3-us3r
date: 2026-04-28
tags:
    - attack.execution
    - attack.discovery
    - attack.t1609
    - attack.t1613
logsource:
    product: kubernetes
    service: audit
detection:
    selection_status:
        responseStatus.code: 'ALLOW'
    selection_request_uri:
        requestURI|contains:
            # Shells Encoded
            - '%2fbin%2fash'
            - '%2fbin%2fbash'
            - '%2fbin%2fbusybox'
            - '%2fbin%2fdash'
            - '%2fbin%2fsh'
            - '%2fbin%2fzsh'
            # Shells Plain
            - '/bin/ash'
            - '/bin/bash'
            - '/bin/busybox'
            - '/bin/dash'
            - '/bin/sh'
            - '/bin/zsh'
            # Tools Encoded
            - '%2fusr%2fbin%2fcurl'
            - '%2fusr%2fbin%2fkubectl'
            - '%2fusr%2fbin%2fperl'
            - '%2fusr%2fbin%2fpython'
            - '%2fusr%2fbin%2fwget'
            # Tools Plain
            - '/usr/bin/curl'
            - '/usr/bin/kubectl'
            - '/usr/bin/perl'
            - '/usr/bin/python'
            - '/usr/bin/wget'
    selection_request_user_agent:
        userAgent|contains:
            - 'access_matrix'  # Rakkess
            - 'trufflehog'     # Secret scanning tool
            - 'azurehound'     # Azure/Cloud discovery
            - 'micro-scanner'  # Vulnerability scanning
    condition: selection_status and 1 of selection_request_*
falsepositives:
    - Authorized administrative maintenance via kubectl
    - Automated internal infrastructure monitoring and certificate rotation
    - Security-approved vulnerability or secret scanning in DevSecOps pipelines
level: medium

Original YAML and metadata in JSON

False positives

• Authorized administrative maintenance via kubectl
• Automated internal infrastructure monitoring and certificate rotation
• Security-approved vulnerability or secret scanning in DevSecOps pipelines

Source references

• https://www.nccgroup.com/research/detection-engineering-for-kubernetes-clusters/
• https://github.com/trufflesecurity/trufflehog
• https://github.com/corneliusweig/rakkess