CVE-2026-66312

HIGHNVD 8.88.8—
EchelonGraph scoreMEDIUM confidence

This high-severity CVE scores 8.8 under NVD CVSS v3. EPSS exploit probability: 0.6%, top 54% of all CVEs by exploit prediction. GitHub Security Advisory enrichment pending alignment with NVD CVSS.

Triggered by: NVD CVSS baseline
Sources: epss, ghsa, nvd
Trending — 4 sources updated this week
8.8EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 1%CVSS: 8.8Exploit: None knownExposed: 0

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

Buffer over-read in Microsoft Edge (Chromium-based) allows an authorized attacker to execute code over a network.

CVSS v3
8.8
EG Score
8.8(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
Severity88% × 45%
Exploitation1% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
1%
EPSS %ILE
46%
KEV
Not listed

Published

August 3, 2026

Last Modified

September 17, 2026

Advisory Details (1)

Auto-updated Aug 3, 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-2026-66312

Vendor Advisories for CVE-2026-66312(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.

All Vendor Advisories

(1)

Every vendor that published an advisory referencing this CVE — pulled from our cve_vendor_advisories aggregation. Click any row for the vendor's original advisory page.

Data Freshness Timeline

(refreshed 35× in last 7d / 157× 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 272 total refreshes for this CVE.

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

Frequently asked(5)

What is CVE-2026-66312?
CVE-2026-66312 is a high vulnerability published on August 3, 2026. Buffer over-read in Microsoft Edge (Chromium-based) allows an authorized attacker to execute code over a network.
When was CVE-2026-66312 disclosed?
CVE-2026-66312 was first published in the National Vulnerability Database on August 3, 2026, with the most recent update on September 17, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-66312 actively exploited?
CVE-2026-66312 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 1% probability of exploitation in the next 30 days, which ranks it in the top 53.8% of all scored CVEs.
What is the CVSS score of CVE-2026-66312?
CVE-2026-66312 has a CVSS v3 base score of 8.8 (NVD).
How do I remediate CVE-2026-66312?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-66312, 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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