GHSA-67R4-FVHF-7VQF

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:

thunderbolt: property: Cap recursion depth in __tb_property_parse_dir()

A DIRECTORY entry's value field is used as the dir_offset for a recursive call into __tb_property_parse_dir() with no depth counter. A crafted peer that chains DIRECTORY entries into a back-reference loop drives the parser until the kernel stack is exhausted and the guard page fires. Any untrusted XDomain peer (cable, dock, in-line inspector, adjacent host) that reaches the PROPERTIES_REQUEST control-plane exchange can trigger this without authentication.

Thread a depth counter through tb_property_parse() and __tb_property_parse_dir(), and reject blocks that exceed TB_PROPERTY_MAX_DEPTH = 8. That is comfortably larger than any observed legitimate XDomain layout.

Operators who do not need XDomain host-to-host discovery can disable the path entirely with thunderbolt.xdomain=0 on the kernel command line.

Show details on source website
To clipboard 

{
  "affected": [],
  "aliases": [
    "CVE-2026-63891"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-07-19T16:17:06Z",
    "severity": null
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nthunderbolt: property: Cap recursion depth in __tb_property_parse_dir()\n\nA DIRECTORY entry\u0027s value field is used as the dir_offset for a\nrecursive call into __tb_property_parse_dir() with no depth counter.\nA crafted peer that chains DIRECTORY entries into a back-reference\nloop drives the parser until the kernel stack is exhausted and the\nguard page fires.  Any untrusted XDomain peer (cable, dock, in-line\ninspector, adjacent host) that reaches the PROPERTIES_REQUEST\ncontrol-plane exchange can trigger this without authentication.\n\nThread a depth counter through tb_property_parse() and\n__tb_property_parse_dir(), and reject blocks that exceed\nTB_PROPERTY_MAX_DEPTH = 8.  That is comfortably larger than any\nobserved legitimate XDomain layout.\n\nOperators who do not need XDomain host-to-host discovery can disable\nthe path entirely with thunderbolt.xdomain=0 on the kernel command\nline.",
  "id": "GHSA-67r4-fvhf-7vqf",
  "modified": "2026-07-19T18:31:44Z",
  "published": "2026-07-19T18:31:44Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-63891"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/0a84ab9271936c11e84e511bb52fc5682f8b6726"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/2b5f47a710172c962ef42d1b732b04d2ad0dce21"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/830c8a9b467e7d3a158483d37fa7dc13892b293a"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/928abe19fbf0127003abcb1ea69cabc1c897d0ab"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/95839a67ea56ca35732aad7f711404a3127cfe2d"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/b4621e5ef63405c317a84b711faf3bd75b3c6a94"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/ed9455ef4bd9babc90f92e526abe3fb68c1a8709"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/f31c6d220f455b5af63590302b30e1b932d14599"
    }
  ],
  "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.