CVE-2026-31735 (GCVE-0-2026-31735)

Vulnerability from cvelistv5 – Published: 2026-05-01 14:14 – Updated: 2026-05-11 22:14
VLAI
Title
iommupt: Fix short gather if the unmap goes into a large mapping
Summary
In the Linux kernel, the following vulnerability has been resolved: iommupt: Fix short gather if the unmap goes into a large mapping unmap has the odd behavior that it can unmap more than requested if the ending point lands within the middle of a large or contiguous IOPTE. In this case the gather should flush everything unmapped which can be larger than what was requested to be unmapped. The gather was only flushing the range requested to be unmapped, not extending to the extra range, resulting in a short invalidation if the caller hits this special condition. This was found by the new invalidation/gather test I am adding in preparation for ARMv8. Claude deduced the root cause. As far as I remember nothing relies on unmapping a large entry, so this is likely not a triggerable bug.
Severity
8.8 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: 7c53f4238aa8bfb476e177263133ead2eeb8d55d , < 50ecd96a28f712f8b682c0441f4cb9b086d28816 (git)
Affected: 7c53f4238aa8bfb476e177263133ead2eeb8d55d , < ee6e69d032550687a3422504bfca3f834c7b5061 (git)
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Linux Linux Affected: 6.19
Unaffected: 0 , < 6.19 (semver)
Unaffected: 6.19.12 , ≤ 6.19.* (semver)
Unaffected: 7.0 , ≤ * (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

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.