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
9.8
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS: 0%CVSS: 9.8Exploit: NoneExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

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)
EPSS
35.9%
KEV
Not listed

Published

May 8, 2026

Last Modified

May 19, 2026

Advisory Details (5)

Auto-updated Jun 21, 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/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/bf4d66d72e4a9e268c1012c331ce9eaedb5e2086
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/960699317d39f46611f4ebeb69edc567c1f4e6b6

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.

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 7× in last 7d / 45× 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 240 total refreshes for this CVE.

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

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 May 19, 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 35.9% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
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

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