CVE-2026-43379

CRITICALNVD 9.89.8—
EchelonGraph scoreMEDIUM confidence

Score 9.8 from GitHub Security Advisory (severity: CRITICAL) published 2026-05-08. NVD baseline CVSS 9.8; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
9.8EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 9.8Exploit: None knownExposed: 0

A fix is available — apply it.

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.

CVSS v3
9.8
EG Score
9.8(medium)
EG Risk
49(Track)
EG Risk 49/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity98% × 45%
Exploitation0% × 40%
Automatability30% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
38%
KEV
Not listed

Published

May 8, 2026

Last Modified

August 5, 2026

Advisory Details (5)

Auto-updated Sep 16, 2026
No patch confirmed yet.
generic

ksmbd: fix use-after-free in smb_lazy_parent_lease_break_close() - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/eac3361e3d5dd8067b3258c69615888eb45e9f25
generic

ksmbd: fix use-after-free in smb_lazy_parent_lease_break_close() - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/b3568347c51c46e2cabc356bc34676df98296619
generic

ksmbd: fix use-after-free in smb_lazy_parent_lease_break_close() - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/dbbd328cf58261ca239756fe1c0d10c9518d3399
generic

ksmbd: fix use-after-free in smb_lazy_parent_lease_break_close() - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/960699317d39f46611f4ebeb69edc567c1f4e6b6
generic

ksmbd: fix use-after-free in smb_lazy_parent_lease_break_close() - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/bf4d66d72e4a9e268c1012c331ce9eaedb5e2086

Vendor Advisories for CVE-2026-43379(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Patch Availability(4)

Vendor / EcosystemFixed in / PatchReleasedSource
ubuntulinux-virtual-6.17 (6.17.0-42.42) @ noble2026-08-23ubuntu
ubuntulinux-tools-oracle-64k-6.17 (6.17.0-1020.20) @ noble2026-08-23ubuntu
ubuntulinux-tools-nvidia-hwe-24.04 (6.17.0-1031.31) @ noble2026-08-23ubuntu
linuxKernel @ 6.6.130—osv

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Affected Packages

(2 across 2 ecosystems)
Debian:13(1)
PackageVulnerable rangeFixed inDependents
linux6.12.38-1 ... 6.12.85-1~bpo12+1 (17 versions)6.12.85-1—
Debian:14(1)
PackageVulnerable rangeFixed inDependents
linux6.12.100-1 ... 6.19~rc8-1~exp1 (122 versions)6.19.10-1—

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

All Vendor Advisories

(3)

Every vendor that published an advisory referencing this CVE — pulled from our cve_vendor_advisories aggregation. Click any row for the vendor's original advisory page.

Data Freshness Timeline

(refreshed 5× in last 7d / 27× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

Showing the most recent 100 of 302 total refreshes for this CVE.

  1. 2026-09-20 20:15 UTCEPSS rescore
  2. 2026-09-18 19:28 UTCEPSS rescore
  3. 2026-09-17 19:31 UTCEPSS rescore
  4. 2026-09-16 14:08 UTCEPSS rescore
  5. 2026-09-16 05:15 UTCEPSS rescore
  6. 2026-09-13 16:47 UTCEPSS rescore
  7. 2026-09-12 15:01 UTCEPSS rescore
  8. 2026-09-11 14:53 UTCEPSS rescore
  9. 2026-09-11 14:23 UTCOSV refresh
  10. 2026-09-11 09:37 UTCEPSS rescore
  11. 2026-09-10 09:34 UTCEPSS rescore
  12. 2026-09-08 22:00 UTCEPSS rescore
  13. 2026-09-07 16:01 UTCEPSS rescore
  14. 2026-09-06 13:47 UTCEPSS rescore
  15. 2026-09-04 05:06 UTCEPSS rescore
  16. 2026-09-02 14:12 UTCEPSS rescore
  17. 2026-09-01 13:54 UTCEPSS rescore
  18. 2026-08-30 19:17 UTCEPSS rescore
  19. 2026-08-30 01:22 UTCEPSS rescore
  20. 2026-08-28 21:41 UTCEPSS rescore
  21. 2026-08-27 14:25 UTCEPSS rescore
  22. 2026-08-26 14:46 UTCEPSS rescore
  23. 2026-08-25 13:49 UTCEPSS rescore
  24. 2026-08-23 19:11 UTCEG score recompute
  25. 2026-08-23 19:11 UTCVendor advisory
Show 75 more
  1. 2026-08-23 19:11 UTCGHSA enrichment
  2. 2026-08-23 00:19 UTCEPSS rescore
  3. 2026-08-21 23:49 UTCEPSS rescore
  4. 2026-08-20 22:55 UTCEPSS rescore
  5. 2026-08-19 17:04 UTCEPSS rescore
  6. 2026-08-18 13:48 UTCEPSS rescore
  7. 2026-08-17 13:47 UTCEPSS rescore
  8. 2026-08-17 11:33 UTCEG score recompute
  9. 2026-08-17 11:33 UTCVendor advisory
  10. 2026-08-17 11:33 UTCGHSA enrichment
  11. 2026-08-16 14:56 UTCEPSS rescore
  12. 2026-08-16 09:09 UTCVendor advisory
  13. 2026-08-16 09:09 UTCGHSA enrichment
  14. 2026-08-16 04:35 UTCEG score recompute
  15. 2026-08-16 04:35 UTCVendor advisory
  16. 2026-08-16 04:35 UTCGHSA enrichment
  17. 2026-08-16 02:14 UTCEPSS rescore
  18. 2026-08-15 01:30 UTCEPSS rescore
  19. 2026-08-15 00:52 UTCVendor advisory
  20. 2026-08-15 00:52 UTCGHSA enrichment
  21. 2026-08-14 20:33 UTCVendor advisory
  22. 2026-08-14 20:33 UTCGHSA enrichment
  23. 2026-08-14 16:07 UTCVendor advisory
  24. 2026-08-14 16:07 UTCGHSA enrichment
  25. 2026-08-14 11:48 UTCVendor advisory
  26. 2026-08-14 11:47 UTCGHSA enrichment
  27. 2026-08-14 07:28 UTCVendor advisory
  28. 2026-08-14 07:28 UTCGHSA enrichment
  29. 2026-08-14 03:09 UTCEG score recompute
  30. 2026-08-14 03:09 UTCVendor advisory
  31. 2026-08-14 03:09 UTCGHSA enrichment
  32. 2026-08-13 22:00 UTCEPSS rescore
  33. 2026-08-13 10:48 UTCVendor advisory
  34. 2026-08-13 10:48 UTCGHSA enrichment
  35. 2026-08-13 05:59 UTCVendor advisory
  36. 2026-08-13 05:59 UTCGHSA enrichment
  37. 2026-08-13 01:37 UTCVendor advisory
  38. 2026-08-13 01:37 UTCGHSA enrichment
  39. 2026-08-12 21:18 UTCVendor advisory
  40. 2026-08-12 21:18 UTCGHSA enrichment
  41. 2026-08-12 16:45 UTCEG score recompute
  42. 2026-08-12 16:45 UTCGHSA enrichment
  43. 2026-08-12 13:51 UTCEPSS rescore
  44. 2026-08-12 00:31 UTCGHSA enrichment
  45. 2026-08-11 20:11 UTCGHSA enrichment
  46. 2026-08-11 15:52 UTCEG score recompute
  47. 2026-08-11 15:52 UTCGHSA enrichment
  48. 2026-08-11 13:43 UTCEPSS rescore
  49. 2026-08-11 10:15 UTCGHSA enrichment
  50. 2026-08-11 05:38 UTCGHSA enrichment
  51. 2026-08-11 01:18 UTCEG score recompute
  52. 2026-08-11 01:18 UTCGHSA enrichment
  53. 2026-08-11 00:00 UTCEPSS rescore
  54. 2026-08-10 13:02 UTCGHSA enrichment
  55. 2026-08-10 08:42 UTCGHSA enrichment
  56. 2026-08-10 04:23 UTCGHSA enrichment
  57. 2026-08-10 00:03 UTCGHSA enrichment
  58. 2026-08-09 19:44 UTCGHSA enrichment
  59. 2026-08-09 15:24 UTCEG score recompute
  60. 2026-08-09 15:24 UTCGHSA enrichment
  61. 2026-08-09 13:46 UTCEPSS rescore
  62. 2026-08-09 11:05 UTCGHSA enrichment
  63. 2026-08-09 06:44 UTCGHSA enrichment
  64. 2026-08-09 02:25 UTCEG score recompute
  65. 2026-08-09 02:25 UTCGHSA enrichment
  66. 2026-08-08 16:37 UTCEPSS rescore
  67. 2026-08-08 10:51 UTCGHSA enrichment
  68. 2026-08-08 06:23 UTCGHSA enrichment
  69. 2026-08-08 02:03 UTCGHSA enrichment
  70. 2026-08-07 21:43 UTCGHSA enrichment
  71. 2026-08-07 17:24 UTCEG score recompute
  72. 2026-08-07 17:24 UTCGHSA enrichment
  73. 2026-08-07 13:04 UTCGHSA enrichment
  74. 2026-08-07 08:44 UTCGHSA enrichment
  75. 2026-08-07 01:44 UTCGHSA enrichment

Related CVEs(same product + same vendor + same CWE)

Frequently asked(5)

What is CVE-2026-43379?
CVE-2026-43379 is a critical vulnerability published on May 8, 2026. In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix use-after-free in smblazyparentleasebreak_close() opinfo pointer obtained via rcudereference(fp->fopinfo) is being accessed after rcureadunlock() has been called. This creates a race condition where the memory could be…
When was CVE-2026-43379 disclosed?
CVE-2026-43379 was first published in the National Vulnerability Database on May 8, 2026, with the most recent update on August 5, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-43379 actively exploited?
CVE-2026-43379 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 62.0% of all scored CVEs.
What is the CVSS score of CVE-2026-43379?
CVE-2026-43379 has a CVSS v3 base score of 9.8 (NVD).
How do I remediate CVE-2026-43379?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-43379, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

See which npm, PyPI, Go, and Maven packages are affected by CVE-2026-43379

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