CVE-2026-46100 (GCVE-0-2026-46100)

Vulnerability from cvelistv5 – Published: 2026-05-27 12:59 – Updated: 2026-08-05 12:29
VLAI
Title
fs: afs: revert mmap_prepare() change
Summary
In the Linux kernel, the following vulnerability has been resolved: fs: afs: revert mmap_prepare() change Partially reverts commit 9d5403b1036c ("fs: convert most other generic_file_*mmap() users to .mmap_prepare()"). This is because the .mmap invocation establishes a refcount, but .mmap_prepare is called at a point where a merge or an allocation failure might happen after the call, which would leak the refcount increment. Functionality is being added to permit the use of .mmap_prepare in this case, but in the interim, we need to fix this.
Severity
7.8 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: 9d5403b1036cdcd4be0f9f5568612c0e60e73d79 , < f51f85c044809fbd39ac8ae07ac99bc43ce32bd5 (git)
Affected: 9d5403b1036cdcd4be0f9f5568612c0e60e73d79 , < 48c7a0eaeea41da17d1d84d2d7a4c40be122b246 (git)
Affected: 9d5403b1036cdcd4be0f9f5568612c0e60e73d79 , < fbfc6578eaca12daa0c09df1e9ba7f2c657b49da (git)
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Linux Linux Affected: 6.17
Unaffected: 0 , < 6.17 (semver)
Unaffected: 6.18.27 , ≤ 6.18.* (semver)
Unaffected: 7.0.4 , ≤ 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.



Related by attack behaviour

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.