Vulnerability-Lookup

GHSA-WVQ8-6V44-2QVW

Vulnerability from github – Published: 2026-05-08 15:31 – Updated: 2026-05-11 09:30

Details

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

ksmbd: fix use-after-free in smb_lazy_parent_lease_break_close()

opinfo pointer obtained via rcu_dereference(fp->f_opinfo) is being accessed after rcu_read_unlock() has been called. This creates a race condition where the memory could be freed by a concurrent writer between the unlock and the subsequent pointer dereferences (opinfo->is_lease, etc.), leading to a use-after-free.

Severity

9.8 (Critical)


                  
                    CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

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{
  "affected": [],
  "aliases": [
    "CVE-2026-43379"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-416"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-05-08T15:16:49Z",
    "severity": "CRITICAL"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: fix use-after-free in smb_lazy_parent_lease_break_close()\n\nopinfo pointer obtained via rcu_dereference(fp-\u003ef_opinfo) is being\naccessed after rcu_read_unlock() has been called. This creates a\nrace condition where the memory could be freed by a concurrent\nwriter between the unlock and the subsequent pointer dereferences\n(opinfo-\u003eis_lease, etc.), leading to a use-after-free.",
  "id": "GHSA-wvq8-6v44-2qvw",
  "modified": "2026-05-11T09:30:31Z",
  "published": "2026-05-08T15:31:26Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-43379"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/960699317d39f46611f4ebeb69edc567c1f4e6b6"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/b3568347c51c46e2cabc356bc34676df98296619"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/bf4d66d72e4a9e268c1012c331ce9eaedb5e2086"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/dbbd328cf58261ca239756fe1c0d10c9518d3399"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/eac3361e3d5dd8067b3258c69615888eb45e9f25"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ]
}

CVE-2026-43379 (GCVE-0-2026-43379)

Vulnerability from cvelistv5 – Published: 2026-05-08 14:21 – Updated: 2026-05-23 16:06

Title

ksmbd: fix use-after-free in smb_lazy_parent_lease_break_close()

Summary

In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix use-after-free in smb_lazy_parent_lease_break_close() opinfo pointer obtained via rcu_dereference(fp->f_opinfo) is being accessed after rcu_read_unlock() has been called. This creates a race condition where the memory could be freed by a concurrent writer between the unlock and the subsequent pointer dereferences (opinfo->is_lease, etc.), leading to a use-after-free.

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/bf4d66d72e4a9e268…
https://git.kernel.org/stable/c/960699317d39f4661…
https://git.kernel.org/stable/c/dbbd328cf58261ca2…
https://git.kernel.org/stable/c/b3568347c51c46e2c…
https://git.kernel.org/stable/c/eac3361e3d5dd8067…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 27b40b7bfcd121fe13a150ffe11957630cf49246 , < bf4d66d72e4a9e268c1012c331ce9eaedb5e2086 (git) Affected: 5fb282ba4fef8985a5acf2b32681f2ec07732561 , < 960699317d39f46611f4ebeb69edc567c1f4e6b6 (git) Affected: 5fb282ba4fef8985a5acf2b32681f2ec07732561 , < dbbd328cf58261ca239756fe1c0d10c9518d3399 (git) Affected: 5fb282ba4fef8985a5acf2b32681f2ec07732561 , < b3568347c51c46e2cabc356bc34676df98296619 (git) Affected: 5fb282ba4fef8985a5acf2b32681f2ec07732561 , < eac3361e3d5dd8067b3258c69615888eb45e9f25 (git) Affected: 6.6.32 , < 6.6.130 (semver)
Linux	Linux	Affected: 6.9 Unaffected: 0 , < 6.9 (semver) Unaffected: 6.6.130 , ≤ 6.6.* (semver) Unaffected: 6.12.78 , ≤ 6.12.* (semver) Unaffected: 6.18.19 , ≤ 6.18.* (semver) Unaffected: 6.19.9 , ≤ 6.19.* (semver) Unaffected: 7.0 , ≤ * (original_commit_for_fix)

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JSON

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{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "fs/smb/server/oplock.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "bf4d66d72e4a9e268c1012c331ce9eaedb5e2086",
              "status": "affected",
              "version": "27b40b7bfcd121fe13a150ffe11957630cf49246",
              "versionType": "git"
            },
            {
              "lessThan": "960699317d39f46611f4ebeb69edc567c1f4e6b6",
              "status": "affected",
              "version": "5fb282ba4fef8985a5acf2b32681f2ec07732561",
              "versionType": "git"
            },
            {
              "lessThan": "dbbd328cf58261ca239756fe1c0d10c9518d3399",
              "status": "affected",
              "version": "5fb282ba4fef8985a5acf2b32681f2ec07732561",
              "versionType": "git"
            },
            {
              "lessThan": "b3568347c51c46e2cabc356bc34676df98296619",
              "status": "affected",
              "version": "5fb282ba4fef8985a5acf2b32681f2ec07732561",
              "versionType": "git"
            },
            {
              "lessThan": "eac3361e3d5dd8067b3258c69615888eb45e9f25",
              "status": "affected",
              "version": "5fb282ba4fef8985a5acf2b32681f2ec07732561",
              "versionType": "git"
            },
            {
              "lessThan": "6.6.130",
              "status": "affected",
              "version": "6.6.32",
              "versionType": "semver"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "fs/smb/server/oplock.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.9"
            },
            {
              "lessThan": "6.9",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.130",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.78",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.19",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.19.*",
              "status": "unaffected",
              "version": "6.19.9",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.0",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.6.130",
                  "versionStartIncluding": "6.6.32",
                  "vulnerable": true
                },
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                  "versionEndExcluding": "6.12.78",
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                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
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                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
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                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.0",
                  "versionStartIncluding": "6.9",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
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          ]
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      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: fix use-after-free in smb_lazy_parent_lease_break_close()\n\nopinfo pointer obtained via rcu_dereference(fp-\u003ef_opinfo) is being\naccessed after rcu_read_unlock() has been called. This creates a\nrace condition where the memory could be freed by a concurrent\nwriter between the unlock and the subsequent pointer dereferences\n(opinfo-\u003eis_lease, etc.), leading to a use-after-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"
          }
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-05-23T16:06:53.273Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/bf4d66d72e4a9e268c1012c331ce9eaedb5e2086"
        },
        {
          "url": "https://git.kernel.org/stable/c/960699317d39f46611f4ebeb69edc567c1f4e6b6"
        },
        {
          "url": "https://git.kernel.org/stable/c/dbbd328cf58261ca239756fe1c0d10c9518d3399"
        },
        {
          "url": "https://git.kernel.org/stable/c/b3568347c51c46e2cabc356bc34676df98296619"
        },
        {
          "url": "https://git.kernel.org/stable/c/eac3361e3d5dd8067b3258c69615888eb45e9f25"
        }
      ],
      "title": "ksmbd: fix use-after-free in smb_lazy_parent_lease_break_close()",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-43379",
    "datePublished": "2026-05-08T14:21:28.027Z",
    "dateReserved": "2026-05-01T14:12:56.006Z",
    "dateUpdated": "2026-05-23T16:06:53.273Z",
    "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.

Action not permitted

GHSA-WVQ8-6V44-2QVW

CVE-2026-43379 (GCVE-0-2026-43379)

Tags

Sightings

Nomenclature