CVE-2026-74711

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: hwmon: (pmbus) Fix type confusion in notification logic Sashiko reports: At the start of the loop in pmbus_notify(), the code unconditionally casts every attribute to a struct sensor_device_attribute: drivers/hwmon/pmbus/pmbus_core.c:pmbus_notify() { for (i = 0; i < data->num_attributes; i++) { struct device_attribute *da = to_dev_attr(data->group.attrs[i]); struct sensor_device_attribute *attr = to_sensor_dev_attr(da); int index = attr->index; ... } However, data->group.attrs can contain other types like struct pmbus_samples_reg or struct pmbus_sensor, which only embed a base struct device_attribute. If da is a struct pmbus_samples_reg, dev_attr is the last member. Casting it to struct sensor_device_attribute and reading the index field appears to access memory past the end of the allocation, which might trigger a slab-out-of-bounds read. Additionally, if da is a struct pmbus_sensor, casting it causes the index field to overlap with the page, phase, and reg fields. Could this produce a garbage mask on little-endian systems that spuriously matches the target reg, page, and flags during an alert? Fix the problem by using struct sensor_device_attr in struct pmbus_sensor and struct pmbus_label. Since those attributes never trigger a notification, set the value of attr->index to -1 for them. Use this value to distinguish from boolean attributes which _can_ trigger a notification and use the index field to encode mask, page, and register values.

Severity

HIGH

CVSS score

8.4 (v3.1)

Vulnerability status

Received

Source identifier

416baaa9-dc9f-4396-8d5f-8c081fb06d67

Published

2026-08-22 16:16:45.853000

Last modified

2026-10-21 13:19:49.343000

View original CVE JSON

{
  "id": "CVE-2026-74711",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-08-22T16:16:45.853",
  "lastModified": "2026-10-21T13:19:49.343",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nhwmon: (pmbus) Fix type confusion in notification logic\n\nSashiko reports:\n\nAt the start of the loop in pmbus_notify(), the code unconditionally casts\nevery attribute to a struct sensor_device_attribute:\n\ndrivers/hwmon/pmbus/pmbus_core.c:pmbus_notify() {\n    for (i = 0; i < data->num_attributes; i++) {\n        struct device_attribute *da = to_dev_attr(data->group.attrs[i]);\n        struct sensor_device_attribute *attr = to_sensor_dev_attr(da);\n        int index = attr->index;\n...\n}\n\nHowever, data->group.attrs can contain other types like struct\npmbus_samples_reg or struct pmbus_sensor, which only embed a base\nstruct device_attribute.\n\nIf da is a struct pmbus_samples_reg, dev_attr is the last member. Casting\nit to struct sensor_device_attribute and reading the index field appears\nto access memory past the end of the allocation, which might trigger a\nslab-out-of-bounds read.\n\nAdditionally, if da is a struct pmbus_sensor, casting it causes the index\nfield to overlap with the page, phase, and reg fields. Could this produce\na garbage mask on little-endian systems that spuriously matches the target\nreg, page, and flags during an alert?\n\nFix the problem by using struct sensor_device_attr in struct pmbus_sensor\nand struct pmbus_label. Since those attributes never trigger a\nnotification, set the value of attr->index to -1 for them. Use this value\nto distinguish from boolean attributes which _can_ trigger a notification\nand use the index field to encode mask, page, and register values."
    },
    {
      "lang": "es",
      "value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\nhwmon: (pmbus) Corrige la confusión de tipos en la lógica de notificación\n\nSashiko informa:\n\nAl inicio del bucle en pmbus_notify(), el código convierte incondicionalmente cada atributo a una struct sensor_device_attribute:\n\ndrivers/hwmon/pmbus/pmbus_core.c:pmbus_notify() {\n    for (i = 0; i < data -> num_attributes; i++) {\n        struct device_attribute da = to_dev_attr(data -> group.attrs[i]);\n        struct sensor_device_attribute attr = to_sensor_dev_attr(da);\n        int index = attr -> index;\n...\n}\n\nSin embargo, data -> group.attrs puede contener otros tipos como struct pmbus_samples_reg o struct pmbus_sensor, que solo incrustan una struct device_attribute base.\n\nSi da es una struct pmbus_samples_reg, dev_attr es el último miembro. Convertirlo a struct sensor_device_attribute y leer el campo index parece acceder a memoria más allá del final de la asignación, lo que podría desencadenar una lectura fuera de límites de slab.\n\nAdemás, si da es una struct pmbus_sensor, convertirlo causa que el campo index se superponga con los campos page, phase y reg. ¿Podría esto producir una máscara de basura en sistemas little-endian que coincida espuriamente con los reg, page y flags objetivo durante una alerta?\n\nSoluciona el problema usando struct sensor_device_attr en struct pmbus_sensor y struct pmbus_label. Dado que esos atributos nunca desencadenan una notificación, establece el valor de attr -> index en -1 para ellos. Usa este valor para distinguir de los atributos booleanos que _sí pueden_ desencadenar una notificación y usan el campo index para codificar los valores de máscara, página y registro."
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "drivers/hwmon/pmbus/pmbus_core.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "f469bde9afd136598a0c4edc054296e6046f90ee",
              "lessThan": "ce443f6827b97e03a0fb34ebfddc8939c85e0500",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "f469bde9afd136598a0c4edc054296e6046f90ee",
              "lessThan": "1c8dd39d48494cceb2c27c1911cbf26d10ce8514",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "f469bde9afd136598a0c4edc054296e6046f90ee",
              "lessThan": "821f6416e69782fa662aff94b5ea52c943042790",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "f469bde9afd136598a0c4edc054296e6046f90ee",
              "lessThan": "0b121de89a99c54bcf516999b04e8531c84f08d5",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "f469bde9afd136598a0c4edc054296e6046f90ee",
              "lessThan": "59bd68ab05a8f9c9a60b6ec44682084184803ff4",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "drivers/hwmon/pmbus/pmbus_core.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "6.4",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "6.4",
              "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": "6.18.45",
              "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:U/C:H/I:H/A:H",
          "baseScore": 8.4,
          "baseSeverity": "HIGH",
          "attackVector": "LOCAL",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 2.5,
        "impactScore": 5.9
      }
    ]
  },
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/0b121de89a99c54bcf516999b04e8531c84f08d5",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/1c8dd39d48494cceb2c27c1911cbf26d10ce8514",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/59bd68ab05a8f9c9a60b6ec44682084184803ff4",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/821f6416e69782fa662aff94b5ea52c943042790",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/ce443f6827b97e03a0fb34ebfddc8939c85e0500",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}