Vulnerability-Lookup

GHSA-PV9X-WP8Q-3X5J

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

Details

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

x86/tdx: Fix off-by-one in port I/O handling

handle_in() and handle_out() in arch/x86/coco/tdx/tdx.c use:

u64 mask = GENMASK(BITS_PER_BYTE * size, 0);

GENMASK(h, l) includes bit h. For size=1 (INB), this produces GENMASK(8, 0) = 0x1FF (9 bits) instead of GENMASK(7, 0) = 0xFF (8 bits). The mask is one bit too wide for all I/O sizes.

Fix the mask calculation.

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{
  "affected": [],
  "aliases": [
    "CVE-2026-89751"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-09-11T20:20:06Z",
    "severity": null
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nx86/tdx: Fix off-by-one in port I/O handling\n\nhandle_in() and handle_out() in arch/x86/coco/tdx/tdx.c use:\n\n    u64 mask = GENMASK(BITS_PER_BYTE * size, 0);\n\nGENMASK(h, l) includes bit h. For size=1 (INB), this produces\nGENMASK(8, 0) = 0x1FF (9 bits) instead of GENMASK(7, 0) = 0xFF (8\nbits). The mask is one bit too wide for all I/O sizes.\n\nFix the mask calculation.",
  "id": "GHSA-pv9x-wp8q-3x5j",
  "modified": "2026-09-14T15:32:36Z",
  "published": "2026-09-11T21:31:39Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-89751"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/0f63e656b1c679d32ac595de29d10c03efca6a25"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/220011fe95fc78b2bc2d7d43893bc73957a5c811"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/222b7005e4519f633b4cd666226256abbab46a1a"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/bb45f705c4440dd3c689328319b88dd28770bbb8"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/c4a22154870813d10aa0b4c734a574c726f9d4b0"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/c6875423ad849ac234ab9812eb72f37ff8a490b4"
    }
  ],
  "schema_version": "1.4.0",
  "severity": []
}

CVE-2026-89751 (GCVE-0-2026-89751)

Vulnerability from cvelistv5 – Published: 2026-09-11 19:46 – Updated: 2026-09-14 12:02

Title

x86/tdx: Fix off-by-one in port I/O handling

Summary

In the Linux kernel, the following vulnerability has been resolved: x86/tdx: Fix off-by-one in port I/O handling handle_in() and handle_out() in arch/x86/coco/tdx/tdx.c use: u64 mask = GENMASK(BITS_PER_BYTE * size, 0); GENMASK(h, l) includes bit h. For size=1 (INB), this produces GENMASK(8, 0) = 0x1FF (9 bits) instead of GENMASK(7, 0) = 0xFF (8 bits). The mask is one bit too wide for all I/O sizes. Fix the mask calculation.

Severity

No CVSS data available.

Assigner

Linux mitre root

References

6 references

URL	Tags
https://git.kernel.org/stable/c/c6875423ad849ac23…
https://git.kernel.org/stable/c/220011fe95fc78b2b…
https://git.kernel.org/stable/c/222b7005e4519f633…
https://git.kernel.org/stable/c/c4a22154870813d10…
https://git.kernel.org/stable/c/bb45f705c4440dd3c…
https://git.kernel.org/stable/c/0f63e656b1c679d32…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 03149948832a078f759022ed5b92e722d8d23c26 , < c6875423ad849ac234ab9812eb72f37ff8a490b4 (git) Affected: 03149948832a078f759022ed5b92e722d8d23c26 , < 220011fe95fc78b2bc2d7d43893bc73957a5c811 (git) Affected: 03149948832a078f759022ed5b92e722d8d23c26 , < 222b7005e4519f633b4cd666226256abbab46a1a (git) Affected: 03149948832a078f759022ed5b92e722d8d23c26 , < c4a22154870813d10aa0b4c734a574c726f9d4b0 (git) Affected: 03149948832a078f759022ed5b92e722d8d23c26 , < bb45f705c4440dd3c689328319b88dd28770bbb8 (git) Affected: 03149948832a078f759022ed5b92e722d8d23c26 , < 0f63e656b1c679d32ac595de29d10c03efca6a25 (git)
Linux	Linux	Affected: 5.19 Unaffected: 0 , < 5.19 (semver) Unaffected: 6.1.188 , ≤ 6.1.* (semver) Unaffected: 6.6.157 , ≤ 6.6.* (semver) Unaffected: 6.12.109 , ≤ 6.12.* (semver) Unaffected: 6.18.50 , ≤ 6.18.* (semver) Unaffected: 7.2.4 , ≤ 7.2.* (semver) Unaffected: 7.3-rc1 , ≤ * (original_commit_for_fix)

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{
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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.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
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