CVE-2026-10670

{
  "id": "CVE-2026-10670",
  "sourceIdentifier": "[email protected]",
  "published": "2026-07-14T15:16:55.330",
  "lastModified": "2026-10-24T21:10:00.130",
  "vulnStatus": "Analyzed",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "The CONFIG_USERSPACE verification handler for the k_thread_name_copy() system call (z_vrfy_k_thread_name_copy() in kernel/thread.c) calls k_object_find() on the caller-supplied thread pointer and then dereferences the returned struct k_object without checking it for NULL. k_object_find() returns NULL whenever the supplied pointer is not a registered (static or dynamic) kernel object.\n\nThe pre-fix guard tested thread == NULL instead of ko == NULL, so an unprivileged user-mode thread that invokes k_thread_name_copy() with any non-NULL but unregistered pointer (e.g. an arbitrary address) passes the NULL test, after which the verifier reads ko->type through a NULL pointer.\n\nBecause the syscall verifier runs in supervisor mode, this NULL dereference is a kernel-mode fault that halts or reboots the system, allowing untrusted user code to crash the kernel across the userspace security boundary (denial of service). The marshaller passes the thread argument to the verifier without any prior K_SYSCALL_OBJ validation, so the bad pointer reaches the defect directly.\n\nThe flaw affects builds with CONFIG_USERSPACE and CONFIG_THREAD_NAME enabled and has been present since the special-case lookup was introduced around v2.0.0; it is present in v4.4.0 and earlier. The fix changes the guard to check the k_object_find() return value (ko == NULL) before dereferencing it."
    },
    {
      "lang": "es",
      "value": "El gestor de verificación CONFIG_USERSPACE para la llamada al sistema k_thread_name_copy() (z_vrfy_k_thread_name_copy() en kernel/thread.c) llama a k_object_find() en el puntero de hilo proporcionado por el llamador y luego desreferencia la struct k_object devuelta sin comprobar si es NULL. k_object_find() devuelve NULL siempre que el puntero proporcionado no sea un objeto kernel registrado (estático o dinámico).\n\nLa protección previa a la corrección probaba thread == NULL en lugar de ko == NULL, por lo que un hilo en modo de usuario sin privilegios que invoca k_thread_name_copy() con cualquier puntero no-NULL pero no registrado (por ejemplo, una dirección arbitraria) pasa la prueba de NULL, después de lo cual el verificador lee ko  ->  type a través de un puntero NULL.\n\nDebido a que el verificador de llamadas al sistema se ejecuta en modo supervisor, esta desreferencia de NULL es un fallo en modo kernel que detiene o reinicia el sistema, permitiendo que código de usuario no confiable bloquee el kernel a través del límite de seguridad del userspace (denegación de servicio). El marshaller pasa el argumento thread al verificador sin ninguna validación previa de K_SYSCALL_OBJ, por lo que el puntero incorrecto llega directamente al defecto.\n\nEl fallo afecta a las compilaciones con CONFIG_USERSPACE y CONFIG_THREAD_NAME habilitados y ha estado presente desde que se introdujo la búsqueda de caso especial alrededor de la v2.0.0; está presente en la v4.4.0 y anteriores. La corrección cambia la protección para comprobar el valor de retorno de k_object_find() (ko == NULL) antes de desreferenciarlo."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "zephyrproject",
          "product": "zephyr",
          "defaultStatus": "unaffected",
          "collectionURL": "https://github.com/zephyrproject-rtos/zephyr",
          "packageName": "zephyr",
          "programFiles": [
            "kernel/thread.c"
          ],
          "versions": [
            {
              "version": "3.7.0",
              "lessThan": "4.3.1",
              "versionType": "semver",
              "status": "affected"
            },
            {
              "version": "4.4.0",
              "lessThan": "4.4.2",
              "versionType": "semver",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
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        "type": "Secondary",
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          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
          "baseScore": 5.5,
          "baseSeverity": "MEDIUM",
          "attackVector": "LOCAL",
          "attackComplexity": "LOW",
          "privilegesRequired": "LOW",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "availabilityImpact": "HIGH"
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        "exploitabilityScore": 1.8,
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        "ssvcData": {
          "timestamp": "2026-07-14T15:30:02.299995Z",
          "id": "CVE-2026-10670",
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            },
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  "weaknesses": [
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      "description": [
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          "lang": "en",
          "value": "CWE-476"
        }
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  "references": [
    {
      "url": "https://github.com/zephyrproject-rtos/zephyr/commit/491583951036bc5794a3843a4baa246453bb1ee2",
      "source": "[email protected]",
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}