CVE-2026-64397 (GCVE-0-2026-64397)

Vulnerability from cvelistv5 – Published: 2026-07-25 08:50 – Updated: 2026-08-17 04:54
VLAI
Title
ksmbd: serialize QUERY_DIRECTORY requests per file
Summary
In the Linux kernel, the following vulnerability has been resolved: ksmbd: serialize QUERY_DIRECTORY requests per file smb2_query_dir() stores a pointer to its stack-allocated private data in the ksmbd_file readdir_data. Concurrent QUERY_DIRECTORY requests using the same file handle can overwrite this pointer while an iterate_dir() callback is still using it, resulting in a stack use-after-free. Add a per-file mutex and hold it while accessing the shared directory enumeration state. The lock covers scan restart, dot entry state, readdir_data setup and iteration, and response construction. This prevents another request from replacing readdir_data.private before the current request has finished using it and also serializes the shared file position.
Severity
9.8 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 , < 1426fd79102539bc0ab5c8fced047ad4313b9908 (git)
Affected: e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 , < 2a64dbf9c739ddf7a25a066507597bf89f8f73d2 (git)
Affected: e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 , < 64dac2d486ec1eb18dc00968b16a230b6b75ec24 (git)
Affected: e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 , < a1d5d31cad593ea5e1b637f2f39c9ef6d09d1199 (git)
Affected: e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 , < fd22b039a5a05bc1d6818e9dcd1001fb432a829d (git)
Affected: e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 , < be6d26bf27499977c746abc163659915082348d8 (git)
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Linux Linux Affected: 5.15
Unaffected: 0 , < 5.15 (semver)
Unaffected: 6.1.178 , ≤ 6.1.* (semver)
Unaffected: 6.6.145 , ≤ 6.6.* (semver)
Unaffected: 6.12.96 , ≤ 6.12.* (semver)
Unaffected: 6.18.39 , ≤ 6.18.* (semver)
Unaffected: 7.1.4 , ≤ 7.1.* (semver)
Unaffected: 7.2 , ≤ * (original_commit_for_fix)
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      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-64397.json",
      "version": "7"
    }
  }
}



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Tags
Taxonomy of the tags.





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.



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.