CVE-2026-40409

HIGHPre-NVD 7.87.8—
EchelonGraph scoreHIGH confidence

Score 7.8 from GitHub Security Advisory (severity: HIGH) published 2026-06-09. the CNA's CVSS baseline 7.8; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: cna:microsoft, epss, ghsa
Trending — 4 sources updated this week
7.8
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS: 0%CVSS: 7.8Exploit: NoneExposed: 0

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

Windows Universal Disk Format File System Driver (UDFS) Elevation of Privilege Vulnerability

CVSS v3
7.8
EG Score
7.8(high)
EPSS
21.5%
KEV
Not listed

Published

June 9, 2026

Last Modified

July 1, 2026

Advisory Details (1)

Auto-updated Jun 9, 2026
Patch available. Sources: microsoft.
microsoft Patch Available

Security Update Guide - Microsoft Security Response Center

Security Update Guide - Microsoft Security Response Center. Patch available via Microsoft Security Update

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-40409

Vendor Advisories for CVE-2026-40409(2)

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 44× in last 7d / 195× 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 195 total refreshes for this CVE.

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

Frequently asked(5)

What is CVE-2026-40409?
CVE-2026-40409 is a high vulnerability published on June 9, 2026. Windows Universal Disk Format File System Driver (UDFS) Elevation of Privilege Vulnerability
When was CVE-2026-40409 disclosed?
CVE-2026-40409 was first published in the National Vulnerability Database on June 9, 2026, with the most recent update on July 1, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-40409 actively exploited?
CVE-2026-40409 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 21.5% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-40409?
CVE-2026-40409 has a CVSS v4.0 base score of 7.8 (CNA self-assessment; NVD's own analysis pending).
How do I remediate CVE-2026-40409?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-40409, 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

Explore the affected products and dependency analysis for CVE-2026-40409

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