CVE-2026-42541

Full vulnerability record from the local CVENow database.

Description

Kubewarden is a policy engine for Kubernetes. Prior to , An attacker with privileged AdmissionPolicy or AdmissionPolicyGroup create permissions (which isn't the default) can craft a policy that makes use of the can_i host callback. The callback issues a SubjectAccessReview (SAR) requests to enumerate RBAC permissions of any user or service account across the cluster. can_i does not perform that check to enforce the context-aware allow-list and forwards the request directly to the callback handler, which executes a real SubjectAccessReview using policy-server privileges. This creates a policy-level authorization gap: can_i is effectively usable even when the policy has no context-aware resource grant. This is an information disclosure / reconnaissance issue, and not direct workload data exfiltration. The attacker learns permission information, such as whether specific service accounts can "get secrets", "create pods", or "bind clusterroles" in chosen namespaces. This vulnerability is fixed in .

Severity

MEDIUM

CVSS score

4.3 (v3.1)

Vulnerability status

Deferred

Source identifier

[email protected]

Published

2026-05-12 18:17:24.957000

Last modified

2026-10-26 18:10:00.173000

View original CVE JSON

{
  "id": "CVE-2026-42541",
  "sourceIdentifier": "[email protected]",
  "published": "2026-05-12T18:17:24.957",
  "lastModified": "2026-10-26T18:10:00.173",
  "vulnStatus": "Deferred",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Kubewarden is a policy engine for Kubernetes. Prior to , An attacker with privileged AdmissionPolicy or AdmissionPolicyGroup create permissions (which isn't the default) can craft a policy that makes use of the can_i host callback. The callback issues a SubjectAccessReview (SAR) requests to enumerate RBAC permissions of any user or service account across the cluster. can_i does not perform that check to enforce the context-aware allow-list and forwards the request directly to the callback handler, which executes a real SubjectAccessReview using policy-server privileges. This creates a policy-level authorization gap: can_i is effectively usable even when the policy has no context-aware resource grant. This is an information disclosure / reconnaissance issue, and not direct workload data exfiltration. The attacker learns permission information, such as whether specific service accounts can \"get secrets\", \"create pods\", or \"bind clusterroles\" in chosen namespaces. This vulnerability is fixed in ."
    },
    {
      "lang": "es",
      "value": "Kubewarden es un motor de políticas para Kubernetes. Antes de , Un atacante con permisos privilegiados de creación de AdmissionPolicy o AdmissionPolicyGroup (lo cual no es el valor predeterminado) puede elaborar una política que utiliza el callback del host can_i. El callback emite solicitudes de SubjectAccessReview (SAR) para enumerar los permisos RBAC de cualquier usuario o cuenta de servicio en todo el clúster. can_i no realiza esa verificación para hacer cumplir la lista de permitidos consciente del contexto y reenvía la solicitud directamente al gestor del callback, que ejecuta un SubjectAccessReview real utilizando los privilegios del servidor de políticas. Esto crea una brecha de autorización a nivel de política: can_i es efectivamente utilizable incluso cuando la política no tiene una concesión de recursos consciente del contexto. Esto es un problema de revelación de información / reconocimiento, y no una exfiltración directa de datos de la carga de trabajo. El atacante aprende información de permisos, como si cuentas de servicio específicas pueden ’obtener secretos’, ’crear pods’ o ’vincular clusterroles’ en los espacios de nombres elegidos. Esta vulnerabilidad está corregida en ."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "kubewarden",
          "product": "kubewarden-controller",
          "versions": [
            {
              "version": "< 1.35.0",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "[email protected]",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N",
          "baseScore": 4.3,
          "baseSeverity": "MEDIUM",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "LOW",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "LOW",
          "integrityImpact": "NONE",
          "availabilityImpact": "NONE"
        },
        "exploitabilityScore": 2.8,
        "impactScore": 1.4
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-05-14T12:23:09.477945Z",
          "id": "CVE-2026-42541",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-862"
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://github.com/kubewarden/adm-controller/security/advisories/GHSA-wqcw-g35j-j578",
      "source": "[email protected]"
    }
  ]
}