CVE-2018-12892

{
  "id": "CVE-2018-12892",
  "cveTags": [],
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          "baseScore": 6.5,
          "accessVector": "NETWORK",
          "vectorString": "AV:N/AC:L/Au:S/C:P/I:P/A:P",
          "authentication": "SINGLE",
          "integrityImpact": "PARTIAL",
          "accessComplexity": "LOW",
          "availabilityImpact": "PARTIAL",
          "confidentialityImpact": "PARTIAL"
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        "acInsufInfo": true,
        "impactScore": 6.4,
        "baseSeverity": "MEDIUM",
        "obtainAllPrivilege": false,
        "exploitabilityScore": 8,
        "obtainUserPrivilege": false,
        "obtainOtherPrivilege": false,
        "userInteractionRequired": false
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          "baseSeverity": "CRITICAL",
          "vectorString": "CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H",
          "integrityImpact": "HIGH",
          "userInteraction": "NONE",
          "attackComplexity": "LOW",
          "availabilityImpact": "HIGH",
          "privilegesRequired": "LOW",
          "confidentialityImpact": "HIGH"
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        "impactScore": 6,
        "exploitabilityScore": 3.1
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  "affected": [
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          "vendor": "n/a",
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              "status": "affected",
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  "published": "2018-07-02T17:29:00.537",
  "references": [
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    {
      "url": "http://xenbits.xen.org/xsa/advisory-266.html",
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    {
      "url": "https://security.gentoo.org/glsa/201810-06",
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      "source": "cve@mitre.org"
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    {
      "url": "https://www.debian.org/security/2018/dsa-4236",
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      "source": "af854a3a-2127-422b-91ae-364da2661108"
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  "vulnStatus": "Modified",
  "weaknesses": [
    {
      "type": "Primary",
      "source": "nvd@nist.gov",
      "description": [
        {
          "lang": "en",
          "value": "CWE-200"
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  ],
  "descriptions": [
    {
      "lang": "en",
      "value": "An issue was discovered in Xen 4.7 through 4.10.x. libxl fails to pass the readonly flag to qemu when setting up a SCSI disk, due to what was probably an erroneous merge conflict resolution. Malicious guest administrators or (in some situations) users may be able to write to supposedly read-only disk images. Only emulated SCSI disks (specified as \"sd\" in the libxl disk configuration, or an equivalent) are affected. IDE disks (\"hd\") are not affected (because attempts to make them readonly are rejected). Additionally, CDROM devices (that is, devices specified to be presented to the guest as CDROMs, regardless of the nature of the backing storage on the host) are not affected; they are always read only. Only systems using qemu-xen (rather than qemu-xen-traditional) as the device model version are vulnerable. Only systems using libxl or libxl-based toolstacks are vulnerable. (This includes xl, and libvirt with the libxl driver.) The vulnerability is present in Xen versions 4.7 and later. (In earlier versions, provided that the patch for XSA-142 has been applied, attempts to create read only disks are rejected.) If the host and guest together usually support PVHVM, the issue is exploitable only if the malicious guest administrator has control of the guest kernel or guest kernel command line."
    },
    {
      "lang": "es",
      "value": "Se ha descubierto un problema en Xen desde la versión 4.7 hasta la 4.10.x. libxl no pasa la marca readonly a qemu al configurar un disco SCSI, debido a lo que probablemente haya sido una resolución de conflicto de unión errónea. Los administradores invitados maliciosos o (en algunos casos) los usuarios podrían ser capaces de escribir en imágenes de disco supuestamente de solo lectura. Solo los discos SCSI emulados (especificados como \"sd\" en la configuración de disco de libxl o equivalentes) se han visto afectados. Los discos IDE (\"hd\") no se han visto afectados, ya que se rechazan los intentos de volverlos discos de solo lectura. Adicionalmente, los dispositivos CDROM (dispositivos especificados para ser presentados al invitado como CDROM, independientemente de la naturaleza del almacenamiento de reserva en el host) no se han visto afectados, ya que siempre son de solo lectura. Solo los sistemas que emplean qemu-xen (en lugar de qemu-xen-traditional) como versión del modelo del dispositivo son vulnerables. Solo los sistemas que emplean las pilas de herramientas de libxl basadas en libxl son vulnerables. (Esto incluye xl y libvirt con el controlador de libxl). La vulnerabilidad está presente en las versiones 4.7 y siguientes de Xen. (En versiones anteriores, si se ha aplicado el parche para XSA-142, los intentos de creación de discos de solo lectura se rechazan). Si el host y el invitado juntos soportan PVHVM, el problema solo es explotable si el administrador invitado tiene el control del kernel invitado o de la línea de comandos del kernel invitado."
    }
  ],
  "lastModified": "2026-06-17T01:38:31.463",
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}