Vulnerability-Lookup

CVE-2026-64383 (GCVE-0-2026-64383)

Vulnerability from cvelistv5 – Published: 2026-07-25 08:50 – Updated: 2026-07-27 05:00

Title

smb: client: fix double-free in SMB2_flush() replay

Summary

In the Linux kernel, the following vulnerability has been resolved: smb: client: fix double-free in SMB2_flush() replay SMB2_flush() keeps its response buffer bookkeeping across replay attempts. If a replayable flush response is received and the retry then fails before cifs_send_recv() stores a replacement response, flush_exit will free the stale response pointer a second time. Reinitialize resp_buftype and rsp_iov at the top of the replay loop so cleanup only acts on response state produced by the current attempt. This fixes a double-free without changing replay handling for successful requests.

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

References

5 references

URL	Tags
https://git.kernel.org/stable/c/6e27f40b682a5e42a…
https://git.kernel.org/stable/c/878757163eea68475…
https://git.kernel.org/stable/c/3407240cde132a4b7…
https://git.kernel.org/stable/c/013a9a3da46c5dabc…
https://git.kernel.org/stable/c/4be31c943a3a27a5a…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 433042a91f9373241307725b52de573933ffedbf , < 6e27f40b682a5e42a2daae3ce6d96f0e0e16dedb (git) Affected: 4f1fffa2376922f3d1d506e49c0fd445b023a28e , < 878757163eea684750107a31ea134c103863515d (git) Affected: 4f1fffa2376922f3d1d506e49c0fd445b023a28e , < 3407240cde132a4b72d6429a2625a09a2f78adaf (git) Affected: 4f1fffa2376922f3d1d506e49c0fd445b023a28e , < 013a9a3da46c5dabcf18f65ea6a47874ba12a15d (git) Affected: 4f1fffa2376922f3d1d506e49c0fd445b023a28e , < 4be31c943a3a27a5a0251dbb8f5cb89059ec3d5a (git) Affected: 6.6.32 , < 6.6.145 (semver)
Linux	Linux	Affected: 6.8 Unaffected: 0 , < 6.8 (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-rc1 , ≤ * (original_commit_for_fix)

Show details on NVD website

JSON

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      "initial_release_date": "2026-07-25T16:00:30Z",
      "source": "SUSE CSAF VEX",
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      "title": "SUSE CVE CVE-2026-64383",
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}

GHSA-J3G4-C7CW-5CH7

Vulnerability from github – Published: 2026-07-25 12:31 – Updated: 2026-07-25 12:31

Details

In the Linux kernel, the following vulnerability has been resolved:

smb: client: fix double-free in SMB2_flush() replay

SMB2_flush() keeps its response buffer bookkeeping across replay attempts. If a replayable flush response is received and the retry then fails before cifs_send_recv() stores a replacement response, flush_exit will free the stale response pointer a second time.

Reinitialize resp_buftype and rsp_iov at the top of the replay loop so cleanup only acts on response state produced by the current attempt. This fixes a double-free without changing replay handling for successful requests.

Show details on source website

JSON

To clipboard

{
  "affected": [],
  "aliases": [
    "CVE-2026-64383"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-07-25T10:17:21Z",
    "severity": null
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nsmb: client: fix double-free in SMB2_flush() replay\n\nSMB2_flush() keeps its response buffer bookkeeping across replay\nattempts. If a replayable flush response is received and the retry then\nfails before cifs_send_recv() stores a replacement response, flush_exit\nwill free the stale response pointer a second time.\n\nReinitialize resp_buftype and rsp_iov at the top of the replay loop so\ncleanup only acts on response state produced by the current attempt.\nThis fixes a double-free without changing replay handling for successful\nrequests.",
  "id": "GHSA-j3g4-c7cw-5ch7",
  "modified": "2026-07-25T12:31:33Z",
  "published": "2026-07-25T12:31:33Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-64383"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/013a9a3da46c5dabcf18f65ea6a47874ba12a15d"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/3407240cde132a4b72d6429a2625a09a2f78adaf"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/4be31c943a3a27a5a0251dbb8f5cb89059ec3d5a"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/6e27f40b682a5e42a2daae3ce6d96f0e0e16dedb"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/878757163eea684750107a31ea134c103863515d"
    }
  ],
  "schema_version": "1.4.0",
  "severity": []
}

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.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.

Action not permitted

CVE-2026-64383 (GCVE-0-2026-64383)

GHSA-J3G4-C7CW-5CH7

Tags

Sightings

Nomenclature