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 mitigationSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0.4%CVSS: 8.4Exploit: None knownExposed services: Not assessed

A fix is referenced (a reference tagged "Patch", often a source commit), but no release containing it is confirmed — find the release that contains it; until it is applied, mitigate (WAF / firewall / segmentation).

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
8.4HIGHmedium confidence
EG Risk
40
EG Risk 40/100

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%
EPSS PROB
0.4%
EPSS %ILE
28th
KEV
Not listed

Published

May 12, 2026

Last Modified

August 10, 2026

Advisory Details (1)

Auto-updated May 12, 2026
Fix referenced — no release confirmed yet. Sources: microsoft.
microsoftMentions a patch (unverified)

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 / 23× 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 287 total refreshes for this CVE.

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

Related CVEs(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 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 0.4% probability of exploitation in the next 30 days (28th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-40364?
CVE-2026-40364 has a CVSS base score of 8.4 (the CNA's own assessment, by microsoft; NVD's own analysis pending).
How do I remediate CVE-2026-40364?
A fix for CVE-2026-40364 is referenced (a reference tagged "Patch", often a source commit), but EchelonGraph has no release containing it on record. Check that reference and the vendor's advisory for a release that contains the fix and update to it; until then, restrict network exposure of the affected system or apply the vendor's mitigation. The vendor advisories EchelonGraph has for CVE-2026-40364 are linked in the Vendor Advisories panel on this page.

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