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
Linux CNA under the mitre root
CNA scorecard D 53/100 over 7018 records in the last 180 days details
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)
guessed Create a notification for this product.
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)
guessed Create a notification for this product.
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      "title": "kernel: ksmbd: serialize QUERY_DIRECTORY requests per file",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-64397.json",
      "version": "3"
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}



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  • 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.
Vulnerability timeline

Sightings and recorded dates, grouped by day · UTC

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