CVE-2026-26109

HIGHPre-NVD 8.48.4—
EchelonGraph scoreMEDIUM confidence

Score 8.4 from GitHub Security Advisory (severity: HIGH) published 2026-03-10. 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: 0%CVSS: 8.4Exploit: None knownExposed: 0

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

Out-of-bounds read in Microsoft Office Excel allows an unauthorized attacker to execute code locally.

CVSS v3
8.4
EG Score
8.4(medium)
EG Risk
38(Track)
EG Risk 38/100SSVC: 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%
Exploitation0% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
35%
KEV
Not listed

Published

March 10, 2026

Last Modified

June 19, 2026

Advisory Details (1)

Auto-updated Jun 23, 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-2026-26109

Vendor Advisories for CVE-2026-26109(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 6× in last 7d / 56× 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 135 total refreshes for this CVE.

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

Related CVEs(same vendor + same CWE)

Frequently asked(5)

What is CVE-2026-26109?
CVE-2026-26109 is a high vulnerability published on March 10, 2026. Out-of-bounds read in Microsoft Office Excel allows an unauthorized attacker to execute code locally.
When was CVE-2026-26109 disclosed?
CVE-2026-26109 was first published in the National Vulnerability Database on March 10, 2026, with the most recent update on June 19, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-26109 actively exploited?
CVE-2026-26109 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 65.2% of all scored CVEs.
What is the CVSS score of CVE-2026-26109?
CVE-2026-26109 has a CVSS v4.0 base score of 8.4 (CNA self-assessment; NVD's own analysis pending).
How do I remediate CVE-2026-26109?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-26109, 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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