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

Vulnerability from cvelistv5 – Published: 2026-09-11 19:46 – Updated: 2026-09-14 12:02
VLAI
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
References
Impacted products
Vendor Product Version CPE status
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)
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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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      "cve": "CVE-2026-89751",
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      "cve": "CVE-2026-89751",
      "id": "CVE-2026-89751",
      "initial_release_date": "2026-09-12T16:22:13Z",
      "source": "SUSE CSAF VEX",
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      "title": "SUSE CVE CVE-2026-89751",
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}



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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

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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.