Vulnerability-Lookup

FKIE_CVE-2026-43379

Vulnerability from fkie_nvd - Published: 2026-05-08 15:16 - Updated: 2026-05-19 19:56

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: 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.

References

URL	Tags
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/960699317d39f46611f4ebeb69edc567c1f4e6b6	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/b3568347c51c46e2cabc356bc34676df98296619	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/bf4d66d72e4a9e268c1012c331ce9eaedb5e2086	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/dbbd328cf58261ca239756fe1c0d10c9518d3399	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/eac3361e3d5dd8067b3258c69615888eb45e9f25	Patch

Impacted products

Vendor	Product	Version
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	7.0
linux	linux_kernel	7.0
linux	linux_kernel	7.0

JSON

To clipboard

{
  "configurations": [
    {
      "nodes": [
        {
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              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
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              "versionStartIncluding": "6.6.32",
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            },
            {
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  ],
  "cveTags": [],
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    {
      "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."
    }
  ],
  "id": "CVE-2026-43379",
  "lastModified": "2026-05-19T19:56:32.510",
  "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": "2026-05-08T15:16:49.100",
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  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-416"
        }
      ],
      "source": "nvd@nist.gov",
      "type": "Primary"
    }
  ]
}

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

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)

Show details on NVD website

JSON

To clipboard

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          "programFiles": [
            "fs/smb/server/oplock.c"
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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

FKIE_CVE-2026-43379

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

Tags

Sightings

Nomenclature