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CVE-2026-64152 (GCVE-0-2026-64152)

Vulnerability from cvelistv5 – Published: 2026-07-19 15:40 – Updated: 2026-08-05 12:39
VLAI
Title
iommu: Handle unmap error when iommu_debug is enabled
Summary
In the Linux kernel, the following vulnerability has been resolved: iommu: Handle unmap error when iommu_debug is enabled Sashiko noticed a latent bug where the map error flow called iommu_unmap() which calls iommu_debug_unmap_begin()/iommu_debug_unmap_end() however since this is an error path the map flow never actually established the original iommu_debug_map() it will malfunction. Lift the unmap error handling into iommu_map_nosync() and reorder it so the trace_map()/iommu_debug_map() records the partial mapping and then immediately unmaps it. This avoid creating the unbalanced tracking and provides saner tracing instead of a unmap unmatched to any map.
Severity
7.8 (High)
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: ccc21213f013834b484cdcc738e282f963fcfc97 , < 0cd028806efc148a75d4acf711d21db335a89661 (git)
Affected: ccc21213f013834b484cdcc738e282f963fcfc97 , < 0735c54804c709d1b292f3b6947cfb560b2ce552 (git)
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Linux Linux Affected: 7.0
Unaffected: 0 , < 7.0 (semver)
Unaffected: 7.0.11 , ≤ 7.0.* (semver)
Unaffected: 7.1 , ≤ * (original_commit_for_fix)
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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.


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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.