CVE-2026-64384 (GCVE-0-2026-64384)
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: smb: client: fix change notify replay double-free A response-bearing attempt can return a replayable error and free its response buffer. If SMB2_notify_init() fails before the next send, cleanup retains the previous buffer type and frees that response again. Reset response bookkeeping before each attempt to prevent the stale free.
References
Impacted products
Vendor Product Version
Linux Linux Version: 433042a91f9373241307725b52de573933ffedbf
Version: 4f1fffa2376922f3d1d506e49c0fd445b023a28e
Version: 4f1fffa2376922f3d1d506e49c0fd445b023a28e
Version: 4f1fffa2376922f3d1d506e49c0fd445b023a28e
Version: 4f1fffa2376922f3d1d506e49c0fd445b023a28e
Version: 6.6.32   ≤
Create a notification for this product.
Show details on NVD website

To clipboard 

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "fs/smb/client/smb2pdu.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "5821f9dbb8b5b24391850a13418e633edd0fb003",
              "status": "affected",
              "version": "433042a91f9373241307725b52de573933ffedbf",
              "versionType": "git"
            },
            {
              "lessThan": "d684f4134998085702009b94c35c2003fc9e72d3",
              "status": "affected",
              "version": "4f1fffa2376922f3d1d506e49c0fd445b023a28e",
              "versionType": "git"
            },
            {
              "lessThan": "52af1975f0dfae990c5a0e85872cc41be0e88a68",
              "status": "affected",
              "version": "4f1fffa2376922f3d1d506e49c0fd445b023a28e",
              "versionType": "git"
            },
            {
              "lessThan": "901891513951bc8322ece754863909ea45af95c6",
              "status": "affected",
              "version": "4f1fffa2376922f3d1d506e49c0fd445b023a28e",
              "versionType": "git"
            },
            {
              "lessThan": "145f820dcbb2cced374f2532f8a61a44dce4a615",
              "status": "affected",
              "version": "4f1fffa2376922f3d1d506e49c0fd445b023a28e",
              "versionType": "git"
            },
            {
              "lessThan": "6.6.145",
              "status": "affected",
              "version": "6.6.32",
              "versionType": "semver"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "fs/smb/client/smb2pdu.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.8"
            },
            {
              "lessThan": "6.8",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.145",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.96",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.39",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.1.*",
              "status": "unaffected",
              "version": "7.1.4",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.2",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.6.145",
                  "versionStartIncluding": "6.6.32",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.12.96",
                  "versionStartIncluding": "6.8",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.39",
                  "versionStartIncluding": "6.8",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.1.4",
                  "versionStartIncluding": "6.8",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.2",
                  "versionStartIncluding": "6.8",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nsmb: client: fix change notify replay double-free\n\nA response-bearing attempt can return a replayable error and free its\nresponse buffer. If SMB2_notify_init() fails before the next send, cleanup\nretains the previous buffer type and frees that response again.\n\nReset response bookkeeping before each attempt to prevent the stale free."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 9.8,
            "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"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:N - A malicious SMB server can return a replayable response and then force reconnect failure over the network, causing the client to free stale response state twice.\nAC:L - The peer controls both prerequisites by returning a status such as STATUS_RETRY and then disconnecting or refusing reconnection; repeated attempts make the scheduling window attacker-controllable.\nPR:N - The malicious SMB peer requires no account, capability, or other privilege on the vulnerable client; the established client session does not grant the attacker privileges on that host.\nUI:N - An ordinary automated CIFS workload can maintain an outstanding change-notify request, after which the remote peer completes the trigger without human involvement.\nS:U - Exploitation compromises the kernel and resources governed by the same host security authority, without crossing a separate virtualization or sandbox boundary.\nC:H - The double-free corrupts the CIFS response-buffer slab or mempool, permitting overlapping live objects and freelist manipulation that can support disclosure of arbitrary kernel memory.\nI:H - The heap corruption can provide attacker-influenced writes through aliased request and response buffers or freelist poisoning, potentially enabling kernel control-flow hijacking.\nA:H - Hardened allocators can immediately panic on the consecutive double-free, while unhardened allocators can crash later through freelist corruption."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-17T04:54:36.154Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/5821f9dbb8b5b24391850a13418e633edd0fb003"
        },
        {
          "url": "https://git.kernel.org/stable/c/d684f4134998085702009b94c35c2003fc9e72d3"
        },
        {
          "url": "https://git.kernel.org/stable/c/52af1975f0dfae990c5a0e85872cc41be0e88a68"
        },
        {
          "url": "https://git.kernel.org/stable/c/901891513951bc8322ece754863909ea45af95c6"
        },
        {
          "url": "https://git.kernel.org/stable/c/145f820dcbb2cced374f2532f8a61a44dce4a615"
        }
      ],
      "title": "smb: client: fix change notify replay double-free",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-64384",
    "datePublished": "2026-07-25T08:50:33.306Z",
    "dateReserved": "2026-07-19T15:36:31.784Z",
    "dateUpdated": "2026-08-17T04:54:36.154Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}


Log in or create an account to share your comment.




Tags
Taxonomy of the tags.




Sightings

Author Source Type Date

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
  • Confirmed: The vulnerability is confirmed from an analyst perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
  • Patched: This vulnerability was successfully patched by the user reporting the sighting.
  • Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
  • Not confirmed: The user expresses doubt about the veracity of the vulnerability.
  • Not patched: This vulnerability was not successfully patched by the user reporting the sighting.