GCVE Workshop - 22 September 2026 (14:00-18:00), Luxembourg Before The Vulnopticon Conference - Registration

GHSA-66MM-3GMH-Q6V8

Vulnerability from github – Published: 2026-09-11 21:31 – Updated: 2026-09-14 15:32
VLAI
Details

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

platform/x86: hp-bioscfg: fix heap OOB read on empty password write

validate_password_input() computes length = strlen(buf) and then checks buf[length - 1] to strip a trailing newline, without checking that length is nonzero first. Writing an empty string (a bare '\n') to current_password or new_password gives length == 0, and buf[length - 1] reads buf[-1], one byte before the heap allocation holding the copied input.

KASAN confirms this directly:

BUG: KASAN: slab-out-of-bounds in store_password_instance.constprop.0+0x223/0x2a0 [hp_bioscfg] Read of size 1 at addr ffff88811bd8da9f by task sh/13740 ... store_password_instance.constprop.0+0x223/0x2a0 [hp_bioscfg] current_password_store+0x14/0x20 [hp_bioscfg] ... The buggy address is located 23 bytes to the right of allocated 8-byte region [ffff88811bd8da80, ffff88811bd8da88)

Reproduced identically via new_password_store. Execution continues past the bad read (the garbage byte only affects whether "length" is decremented by one), so the write completes and returns success; this is a pure information read past the buffer, not a crash, but it is still an out-of-bounds access KASAN correctly flags.

Fix by only checking buf[length - 1] when length is nonzero.

Show details on source website
To clipboard 

{
  "affected": [],
  "aliases": [
    "CVE-2026-81013"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-09-11T20:19:10Z",
    "severity": null
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nplatform/x86: hp-bioscfg: fix heap OOB read on empty password write\n\nvalidate_password_input() computes length = strlen(buf) and then\nchecks buf[length - 1] to strip a trailing newline, without checking\nthat length is nonzero first. Writing an empty string (a bare \u0027\\n\u0027)\nto current_password or new_password gives length == 0, and\nbuf[length - 1] reads buf[-1], one byte before the heap allocation\nholding the copied input.\n\nKASAN confirms this directly:\n\n  BUG: KASAN: slab-out-of-bounds in store_password_instance.constprop.0+0x223/0x2a0 [hp_bioscfg]\n  Read of size 1 at addr ffff88811bd8da9f by task sh/13740\n  ...\n  store_password_instance.constprop.0+0x223/0x2a0 [hp_bioscfg]\n  current_password_store+0x14/0x20 [hp_bioscfg]\n  ...\n  The buggy address is located 23 bytes to the right of\n  allocated 8-byte region [ffff88811bd8da80, ffff88811bd8da88)\n\nReproduced identically via new_password_store. Execution continues\npast the bad read (the garbage byte only affects whether \"length\" is\ndecremented by one), so the write completes and returns success; this\nis a pure information read past the buffer, not a crash, but it is\nstill an out-of-bounds access KASAN correctly flags.\n\nFix by only checking buf[length - 1] when length is nonzero.",
  "id": "GHSA-66mm-3gmh-q6v8",
  "modified": "2026-09-14T15:32:23Z",
  "published": "2026-09-11T21:31:24Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-81013"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/0f9aad08424882dd5714b53d29ae044060890752"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/21243c15e1d31f0df1517435e3a7784747f19043"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/2b2ec354f905c14e3270e8ec3ab50f7d8ad73bab"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/b699e5c1f63a9e79946c35598c8a6f7af2c356b8"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/cecb8154bd5fa6c8ddbd1a4e8216bbc0f0eb9828"
    }
  ],
  "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.


Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.