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CVE-2026-64151 (GCVE-0-2026-64151)

Vulnerability from cvelistv5 – Published: 2026-07-19 15:40 – Updated: 2026-08-05 12:39
VLAI
Title
iommupt: Check for missing PAGE_SIZE in the pgsize_bitmap
Summary
In the Linux kernel, the following vulnerability has been resolved: iommupt: Check for missing PAGE_SIZE in the pgsize_bitmap Sashiko pointed out that the driver could drop PAGE_SIZE from the pgsize_bitmap. That is technically allowed but nothing does it, and such an iommu_domain would not be used with the DMA API today. Still, it is against the design and it is trivial to fix up. Lift the PT_WARN_ON to the if branch and just skip the fast path.
Severity
8.4 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: dcd6a011a8d523a114af2360a8753de5bd60c139 , < 00850f41da24423587abd6124a790dd4f12bcef3 (git)
Affected: dcd6a011a8d523a114af2360a8753de5bd60c139 , < 8ef3f77c440005c7f04229a75976bfc078364247 (git)
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Linux Linux Affected: 6.19
Unaffected: 0 , < 6.19 (semver)
Unaffected: 7.0.11 , ≤ 7.0.* (semver)
Unaffected: 7.1 , ≤ * (original_commit_for_fix)
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    "redhat_vex": {
      "aggregate_severity": "Moderate",
      "current_release_date": "2026-08-18T15:51:49+00:00",
      "cve": "CVE-2026-64151",
      "id": "CVE-2026-64151",
      "initial_release_date": "2026-07-19T00:00:00+00:00",
      "product_status:known_not_affected": "274",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: iommupt: Check for missing PAGE_SIZE in the pgsize_bitmap",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-64151.json",
      "version": "3"
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}



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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.
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  • 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.


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