CVE-2026-64397 (GCVE-0-2026-64397)
Vulnerability from cvelistv5
Published
2026-07-25 08:50
Modified
2026-08-17 04:54
Severity ?
9.8 (Critical) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
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.
References
Impacted products
Vendor Product Version
Linux Linux Version: e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9
Version: e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9
Version: e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9
Version: e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9
Version: e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9
Version: e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9
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          "programFiles": [
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      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: serialize QUERY_DIRECTORY requests per file\n\nsmb2_query_dir() stores a pointer to its stack-allocated private data in\nthe ksmbd_file readdir_data. Concurrent QUERY_DIRECTORY requests using the\nsame file handle can overwrite this pointer while an iterate_dir() callback\nis still using it, resulting in a stack use-after-free.\n\nAdd a per-file mutex and hold it while accessing the shared directory\nenumeration state. The lock covers scan restart, dot entry state,\nreaddir_data setup and iteration, and response construction. This prevents\nanother request from replacing readdir_data.private before the current\nrequest has finished using it and also serializes the shared file position."
        }
      ],
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            "baseSeverity": "CRITICAL",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
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            }
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      "providerMetadata": {
        "dateUpdated": "2026-08-17T04:54:51.854Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
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          "url": "https://git.kernel.org/stable/c/1426fd79102539bc0ab5c8fced047ad4313b9908"
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        {
          "url": "https://git.kernel.org/stable/c/2a64dbf9c739ddf7a25a066507597bf89f8f73d2"
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        },
        {
          "url": "https://git.kernel.org/stable/c/be6d26bf27499977c746abc163659915082348d8"
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      ],
      "title": "ksmbd: serialize QUERY_DIRECTORY requests per file",
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  "cveMetadata": {
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    "assignerShortName": "Linux",
    "cveId": "CVE-2026-64397",
    "datePublished": "2026-07-25T08:50:41.620Z",
    "dateReserved": "2026-07-19T15:36:31.785Z",
    "dateUpdated": "2026-08-17T04:54:51.854Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}


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