CVE-2026-13434

{
  "id": "CVE-2026-13434",
  "sourceIdentifier": "[email protected]",
  "published": "2026-06-26T17:16:32.313",
  "lastModified": "2026-10-25T17:10:00.197",
  "vulnStatus": "Analyzed",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "A flaw was found in KubeVirt's network annotation generator. When a tenant creates a VirtualMachineInstance with a Multus network configuration, the supplied networkName value is written verbatim into the launcher pod's v1.multus-cni.io/default-network annotation without format validation or sanitization. The only admission check rejects empty strings; no DNS-1123 format validation, JSON detection, or special character rejection is performed. When the ExternalNetResourceInjection Beta feature gate is enabled (off by default, cluster-admin only), the NAD lookup that would otherwise catch malformed names is skipped by design. A tenant with kubevirt.io:edit permissions can inject a JSON-formatted NetworkSelectionElement array specifying an arbitrary namespace, NAD name, static IP address, and MAC address. Multus on the node parses this JSON and attaches the launcher pod to the specified network attachment in any namespace, enabling cross-namespace network access and IP/MAC impersonation on network segments normally segregated from tenant workloads. The ExternalNetResourceInjection feature gate was introduced in KubeVirt v1.8.0 (first shipped in OpenShift Virtualization 4.21)."
    },
    {
      "lang": "es",
      "value": "Se encontró un fallo en el generador de anotaciones de red de KubeVirt. Cuando un inquilino crea una VirtualMachineInstance con una configuración de red Multus, el valor networkName proporcionado se escribe textualmente en la anotación v1.multus-cni.io/default-network del pod lanzador sin validación de formato ni saneamiento. La única comprobación de admisión rechaza cadenas vacías; no se realiza validación de formato DNS-1123, detección de JSON ni rechazo de caracteres especiales. Cuando la puerta de características Beta ExternalNetResourceInjection está habilitada (deshabilitada por defecto, solo para administradores de clúster), la búsqueda de NAD que de otro modo detectaría nombres mal formados se omite por diseño. Un inquilino con permisos kubevirt.io:edit puede inyectar una matriz NetworkSelectionElement con formato JSON especificando un espacio de nombres arbitrario, nombre de NAD, dirección IP estática y dirección MAC. Multus en el nodo analiza este JSON y adjunta el pod lanzador a la conexión de red especificada en cualquier espacio de nombres, lo que permite el acceso a la red entre espacios de nombres e impersonación de IP/MAC en segmentos de red normalmente segregados de las cargas de trabajo de los inquilinos. La puerta de características ExternalNetResourceInjection se introdujo en KubeVirt v1.8.0 (distribuida por primera vez en OpenShift Virtualization 4.21)."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "Red Hat",
          "product": "Red Hat OpenShift Virtualization 4",
          "defaultStatus": "affected",
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "packageName": "container-native-virtualization/virt-controller-rhel9",
          "cpes": [
            "cpe:/a:redhat:container_native_virtualization:4"
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "[email protected]",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:L/I:L/A:N",
          "baseScore": 4.9,
          "baseSeverity": "MEDIUM",
          "attackVector": "NETWORK",
          "attackComplexity": "HIGH",
          "privilegesRequired": "LOW",
          "userInteraction": "NONE",
          "scope": "CHANGED",
          "confidentialityImpact": "LOW",
          "integrityImpact": "LOW",
          "availabilityImpact": "NONE"
        },
        "exploitabilityScore": 1.8,
        "impactScore": 2.7
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-06-27T02:38:10.829887Z",
          "id": "CVE-2026-13434",
          "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-20"
        }
      ]
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "operator": "OR",
          "negate": false,
          "cpeMatch": [
            {
              "vulnerable": true,
              "criteria": "cpe:2.3:a:kubevirt:kubevirt:-:*:*:*:*:kubernetes:*:*",
              "matchCriteriaId": "06AF9668-6158-47F4-A755-0EE4D5F7F413"
            },
            {
              "vulnerable": true,
              "criteria": "cpe:2.3:a:redhat:openshift_virtualization:*:*:*:*:*:*:*:*",
              "versionStartIncluding": "4",
              "versionEndIncluding": "4.22.0",
              "matchCriteriaId": "5301905C-9B5C-479F-A69A-659C6CB3AA42"
            }
          ]
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://access.redhat.com/security/cve/CVE-2026-13434",
      "source": "[email protected]",
      "tags": [
        "Mitigation",
        "Vendor Advisory"
      ]
    },
    {
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2493576",
      "source": "[email protected]",
      "tags": [
        "Vendor Advisory",
        "Issue Tracking"
      ]
    }
  ]
}