Minimize the admission of root containers

ID: k8s-root-container-admission

Severity: critical

Author: princechaddha

Tags: cloud,devops,kubernetes,devsecops,deployments,k8s,k8s-cluster-security

Description

Checks if any Kubernetes Deployments admit containers that run as root, which can pose a significant security risk.

YAML Source

id: k8s-root-container-admission

info:
  name: Minimize the admission of root containers
  author: princechaddha
  severity: critical
  description: Checks if any Kubernetes Deployments admit containers that run as root, which can pose a significant security risk.
  impact: |
    Allowing containers to run as root can lead to privilege escalation and unauthorized access to host resources, significantly compromising the security of the cluster.
  remediation: |
    Configure security contexts for all pods to run containers with a non-root user. Use Pod Security Policies or OPA/Gatekeeper to enforce these configurations.
  reference:
    - https://kubernetes.io/docs/concepts/policy/pod-security-policy/#users-and-groups
  tags: cloud,devops,kubernetes,devsecops,deployments,k8s,k8s-cluster-security

flow: |
  code(1);
  for (let deployment of template.items) {
    set("deployment", deployment)
    javascript(1);
  }

self-contained: true
code:
  - engine:
      - sh
      - bash
    source: kubectl get deployments --all-namespaces --output=json
    extractors:
      - type: json
        name: items
        internal: true
        json:
          - '.items[]'

javascript:
  - code: |
        deployment = JSON.parse(template.deployment);
        if (deployment.spec.template.spec.containers.some(container => container.securityContext && container.securityContext.runAsUser === null)) {
          let result = (`Deployment '${deployment.metadata.name}' in namespace '${deployment.metadata.namespace}' permits containers to run as root.`);
          Export(result);
        }

    extractors:
      - type: dsl
        dsl:
          - response
# digest: 4a0a0047304502205299c4220e84ac81f35481c96a849779a6cb30311ac8e35a9b50f3711ec6976302210088c44a7ad3975409e66a02ea174236f7caf672c2d232abe22d821fa4ee2ecc39:922c64590222798bb761d5b6d8e72950

Guide to check the vulnerabilities

This template is used to detect vulnerabilities in web applications. It can be used with the Nuclei tool to scan for specific patterns or behaviors.

$ nuclei -u "URL" -t "cloud/kubernetes/deployments/k8s-root-container-admission.yaml"

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