Vulnerability-Lookup

FKIE_CVE-2026-64383

Vulnerability from fkie_nvd - Published: 2026-07-25 10:17 - Updated: 2026-09-04 20:46

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: 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.

References

URL	Tags
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/013a9a3da46c5dabcf18f65ea6a47874ba12a15d	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/3407240cde132a4b72d6429a2625a09a2f78adaf	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/4be31c943a3a27a5a0251dbb8f5cb89059ec3d5a	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/6e27f40b682a5e42a2daae3ce6d96f0e0e16dedb	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/878757163eea684750107a31ea134c103863515d	Patch

Impacted products

Vendor	Product	Version
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	6.8
linux	linux_kernel	6.8
linux	linux_kernel	6.8
linux	linux_kernel	6.8
linux	linux_kernel	6.8
linux	linux_kernel	6.8
linux	linux_kernel	6.8

JSON

To clipboard

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "fs/smb/client/smb2pdu.c"
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      "lang": "en",
      "value": "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": "CVE-2026-64383",
  "lastModified": "2026-09-04T20:46:44.003",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 9.8,
          "baseSeverity": "CRITICAL",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 5.9,
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "type": "Secondary"
      }
    ]
  },
  "published": "2026-07-25T10:17:21.587",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
        "Patch"
      ],
      "url": "https://git.kernel.org/stable/c/013a9a3da46c5dabcf18f65ea6a47874ba12a15d"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
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  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-415"
        }
      ],
      "source": "nvd@nist.gov",
      "type": "Primary"
    }
  ]
}

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

Vulnerability from cvelistv5 – Published: 2026-07-25 08:50 – Updated: 2026-08-17 04:54

Title

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

Summary

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 mitre root

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 , ≤ * (original_commit_for_fix)

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "fs/smb/client/smb2pdu.c"
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            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-17T04:54:35.045Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
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        },
        {
          "url": "https://git.kernel.org/stable/c/4be31c943a3a27a5a0251dbb8f5cb89059ec3d5a"
        }
      ],
      "title": "smb: client: fix double-free in SMB2_flush() replay",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-64383",
    "datePublished": "2026-07-25T08:50:32.634Z",
    "dateReserved": "2026-07-19T15:36:31.784Z",
    "dateUpdated": "2026-08-17T04:54:35.045Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

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.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

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.