GHSA-9794-J36C-V322

Vulnerability from github – Published: 2026-07-19 18:31 – Updated: 2026-07-19 18:31
VLAI
Details

In the Linux kernel, the following vulnerability has been resolved:

hwmon: (pmbus/adm1266) reject short block-read responses in the GPIO accessors

adm1266_gpio_get() and adm1266_gpio_get_multiple() both compose the pin-status word as

pins_status = read_buf[0] + (read_buf[1] << 8);

right after i2c_smbus_read_block_data(), guarding only against an error return. A well-behaved device returns 2 bytes for GPIO_STATUS/PDIO_STATUS, but the helper happily reports a 0- or 1-byte response too. If the device returns 0 bytes, both read_buf slots are uninitialized stack memory; if it returns 1 byte, read_buf[1] is.

The composed value then flows through set_bit() into the caller's *bits in adm1266_gpio_get_multiple(), or into the return value of adm1266_gpio_get(), and ends up in userspace via gpiolib (sysfs and the char-dev ioctls). That leaks a few bits of kernel stack per request on any device whose firmware glitch, bus error, or hostile slave produces a short block-read response.

Add the missing length check to both call sites and surface a short response as -EIO.

Show details on source website
To clipboard 

{
  "affected": [],
  "aliases": [
    "CVE-2026-64083"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-07-19T16:17:48Z",
    "severity": null
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nhwmon: (pmbus/adm1266) reject short block-read responses in the GPIO accessors\n\nadm1266_gpio_get() and adm1266_gpio_get_multiple() both compose the\npin-status word as\n\n\tpins_status = read_buf[0] + (read_buf[1] \u003c\u003c 8);\n\nright after i2c_smbus_read_block_data(), guarding only against an\nerror return.  A well-behaved device returns 2 bytes for\nGPIO_STATUS/PDIO_STATUS, but the helper happily reports a 0- or\n1-byte response too.  If the device returns 0 bytes, both read_buf\nslots are uninitialized stack memory; if it returns 1 byte, read_buf[1]\nis.\n\nThe composed value then flows through set_bit() into the caller\u0027s\n*bits in adm1266_gpio_get_multiple(), or into the return value of\nadm1266_gpio_get(), and ends up in userspace via gpiolib (sysfs and\nthe char-dev ioctls).  That leaks a few bits of kernel stack per\nrequest on any device whose firmware glitch, bus error, or hostile\nslave produces a short block-read response.\n\nAdd the missing length check to both call sites and surface a short\nresponse as -EIO.",
  "id": "GHSA-9794-j36c-v322",
  "modified": "2026-07-19T18:31:51Z",
  "published": "2026-07-19T18:31:51Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-64083"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/64fa9328948ddcc0f7f3c23ea1756c126d9dffac"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/a2d1c819348b36fccbbfcf37c5fa7a50a9b4528f"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/a7232f68c43ca62f545049b7f5fbfc75137b843b"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/ae25cf2ea9ebd06d7ad416647dbdc7b5d0172946"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/c603b6c6840ac0c6285f5eefea0de6242710af21"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/eb3cd9bb590460c6127145cb245be925d23f5232"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/ee4799becf7d2af3778007e22c2e55c4009a49c7"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/fd9196aad9e5a3845cea17de3405ebc700382142"
    }
  ],
  "schema_version": "1.4.0",
  "severity": []
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.





Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.