CVE-2026-74713

{
  "id": "CVE-2026-74713",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-08-22T16:16:46.063",
  "lastModified": "2026-10-30T13:20:04.460",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nvhost_iotlb: bound map allocation in add_range\n\nvhost_iotlb_add_range_ctx() only retires an old entry when the table\nhas a non-zero limit, has exactly reached that limit and has\nVHOST_IOTLB_FLAG_RETIRE set. Non-retiring tables can keep allocating\nentries after reaching their configured limit.\n\nExisting vhost devices allocate their IOTLB with max_iotlb_entries from\nvhost.c, which defaults to 2048 and is tunable by module parameter. Use\nthe caller-provided limit at the allocation point instead of adding a\nseparate default in the common IOTLB helper, and reject non-positive\nvalues in vhost paths that can report an error.\n\nOther vhost IOTLB users should not create zero-limit tables when entries\ncan be populated from userspace or guest-controlled requests. Add\ncaller-side max_iotlb_entries parameters for mlx5 vDPA, VDUSE and\nvhost-vDPA. Reject non-positive VDUSE and vhost-vDPA values, and require\nat least two entries for vdpa_sim and mlx5 vDPA paths that install\nfull-range mappings, since those mappings are split into two IOTLB\nentries.\n\nHandle full-range mappings in the common helper by checking that the\nIOTLB can hold both split entries before inserting the first half. This\navoids returning an error after leaving a half mapping behind.\n\nWhen the table is full, keep the existing retire behavior for retiring\ntables and return -ENOSPC for non-retiring tables. Reuse the retired map\nnode instead of freeing it and allocating a replacement, so a stream of\nIOTLB updates cannot keep forcing GFP_ATOMIC allocations after the table\nhas reached its limit. If a zero-limit IOTLB still reaches the common\nhelper, treat it as a configuration error and return -EINVAL.\n\nI found this bug myself, though the patch was written with AI assistance."
    },
    {
      "lang": "es",
      "value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\nvhost_iotlb: asignación de mapa limitada en add_range\n\nvhost_iotlb_add_range_ctx() solo retira una entrada antigua cuando la tabla tiene un límite no nulo, ha alcanzado exactamente ese límite y tiene VHOST_IOTLB_FLAG_RETIRE establecido. Las tablas que no retiran pueden seguir asignando entradas después de alcanzar su límite configurado.\n\nLos dispositivos vhost existentes asignan su IOTLB con max_iotlb_entries de vhost.c, que por defecto es 2048 y es configurable mediante un parámetro de módulo. Utilice el límite proporcionado por el llamador en el punto de asignación en lugar de añadir un valor predeterminado separado en el asistente IOTLB común, y rechace los valores no positivos en las rutas vhost que pueden informar un error.\n\nOtros usuarios de IOTLB de vhost no deben crear tablas de límite cero cuando las entradas pueden ser pobladas desde el espacio de usuario o solicitudes controladas por el invitado. Añada parámetros max_iotlb_entries del lado del llamador para mlx5 vDPA, VDUSE y vhost-vDPA. Rechace los valores no positivos de VDUSE y vhost-vDPA, y requiera al menos dos entradas para las rutas vdpa_sim y mlx5 vDPA que instalan mapeos de rango completo, ya que esos mapeos se dividen en dos entradas IOTLB.\n\nManeje los mapeos de rango completo en el asistente común verificando que el IOTLB puede contener ambas entradas divididas antes de insertar la primera mitad. Esto evita devolver un error después de dejar un mapeo a medias.\n\nCuando la tabla está llena, mantenga el comportamiento de retiro existente para las tablas que retiran y devuelva -ENOSPC para las tablas que no retiran. Reutilice el nodo de mapa retirado en lugar de liberarlo y asignar un reemplazo, para que un flujo de actualizaciones de IOTLB no pueda seguir forzando asignaciones GFP_ATOMIC después de que la tabla haya alcanzado su límite. Si un IOTLB de límite cero aún llega al asistente común, trátelo como un error de configuración y devuelva -EINVAL.\n\nEncontré este error yo mismo, aunque el parche fue escrito con asistencia de IA."
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "drivers/vdpa/mlx5/core/mlx5_vdpa.h",
            "drivers/vdpa/mlx5/core/mr.c",
            "drivers/vdpa/mlx5/core/resources.c",
            "drivers/vdpa/vdpa_sim/vdpa_sim.c",
            "drivers/vdpa/vdpa_user/iova_domain.c",
            "drivers/vhost/iotlb.c",
            "drivers/vhost/vdpa.c",
            "drivers/vhost/vhost.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "0bbe30668d89ec8a309f28ced6d092c90fb23e8c",
              "lessThan": "91d3f1fcb8f7109f18d46a7366bb8202ac4b4456",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "0bbe30668d89ec8a309f28ced6d092c90fb23e8c",
              "lessThan": "96da3e1439e7d689eea09fc9b6227fbab5b88ac3",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "0bbe30668d89ec8a309f28ced6d092c90fb23e8c",
              "lessThan": "eb70200e34772572ad08e99291b08afea6522111",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "0bbe30668d89ec8a309f28ced6d092c90fb23e8c",
              "lessThan": "b57164cdddb46924ff9fa191b727ca097744de88",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "0bbe30668d89ec8a309f28ced6d092c90fb23e8c",
              "lessThan": "ae128dd19040ee06a4f8143c7ced4d18080d7a9a",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "0bbe30668d89ec8a309f28ced6d092c90fb23e8c",
              "lessThan": "1ed35ac7f3fe2b4396bdd29ac3a7f0ebc0829e94",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "drivers/vdpa/mlx5/core/mlx5_vdpa.h",
            "drivers/vdpa/mlx5/core/mr.c",
            "drivers/vdpa/mlx5/core/resources.c",
            "drivers/vdpa/vdpa_sim/vdpa_sim.c",
            "drivers/vdpa/vdpa_user/iova_domain.c",
            "drivers/vhost/iotlb.c",
            "drivers/vhost/vdpa.c",
            "drivers/vhost/vhost.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "5.7",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "5.7",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.1.191",
              "lessThanOrEqual": "6.1.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.6.160",
              "lessThanOrEqual": "6.6.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.12.114",
              "lessThanOrEqual": "6.12.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.18.57",
              "lessThanOrEqual": "6.18.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.1.9",
              "lessThanOrEqual": "7.1.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2",
              "lessThanOrEqual": "*",
              "versionType": "original_commit_for_fix",
              "status": "unaffected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H",
          "baseScore": 7.1,
          "baseSeverity": "HIGH",
          "attackVector": "LOCAL",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "scope": "CHANGED",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 2.5,
        "impactScore": 4.0
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-10-16T19:15:21.643384Z",
          "id": "CVE-2026-74713",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/1ed35ac7f3fe2b4396bdd29ac3a7f0ebc0829e94",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/91d3f1fcb8f7109f18d46a7366bb8202ac4b4456",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/96da3e1439e7d689eea09fc9b6227fbab5b88ac3",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/ae128dd19040ee06a4f8143c7ced4d18080d7a9a",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/b57164cdddb46924ff9fa191b727ca097744de88",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/eb70200e34772572ad08e99291b08afea6522111",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}