CVE-2026-40364

HIGHPre-NVD 8.48.4—
EchelonGraph scoreMEDIUM confidence

Score 8.4 from GitHub Security Advisory (severity: HIGH) published 2026-05-12. the CNA's CVSS baseline 8.4; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: cna:microsoft, epss, ghsa
8.4EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 4%CVSS: 8.4Exploit: None knownExposed: 0

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

Access of resource using incompatible type ('type confusion') in Microsoft Office Word allows an unauthorized attacker to execute code locally.

CVSS v3
8.4
EG Score
8.4(medium)
EG Risk
40(Track)
EG Risk 40/100SSVC: 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
Severity84% × 45%
Exploitation4% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
4%
EPSS %ILE
91%
KEV
Not listed

Published

May 12, 2026

Last Modified

August 10, 2026

Advisory Details (1)

Auto-updated May 12, 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-2026-40364

Vendor Advisories for CVE-2026-40364(1)

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

Weakness Classification(3)

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

Data Freshness Timeline

(refreshed 7× in last 7d / 29× 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 274 total refreshes for this CVE.

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

Related CVEs(same vendor + same CWE)

Frequently asked(5)

What is CVE-2026-40364?
CVE-2026-40364 is a high vulnerability published on May 12, 2026. Access of resource using incompatible type ('type confusion') in Microsoft Office Word allows an unauthorized attacker to execute code locally.
When was CVE-2026-40364 disclosed?
CVE-2026-40364 was first published in the National Vulnerability Database on May 12, 2026, with the most recent update on August 10, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-40364 actively exploited?
CVE-2026-40364 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 4% probability of exploitation in the next 30 days, which ranks it in the top 9.1% of all scored CVEs.
What is the CVSS score of CVE-2026-40364?
CVE-2026-40364 has a CVSS v4.0 base score of 8.4 (CNA self-assessment; NVD's own analysis pending).
How do I remediate CVE-2026-40364?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-40364, 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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