CVE-2026-66312

HIGHNVD 8.88.8—
EchelonGraph scoreMEDIUM confidence

This high-severity CVE scores 8.8 under NVD CVSS v3. EPSS exploit probability: 1.1%, top 37% 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
63%
KEV
Not listed

Published

August 3, 2026

Last Modified

August 20, 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 48× in last 7d / 119× 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 119 total refreshes for this CVE.

  1. 2026-08-21 04:39 UTCEG score recompute
  2. 2026-08-21 04:39 UTCVendor advisory
  3. 2026-08-21 04:39 UTCGHSA enrichment
  4. 2026-08-20 22:56 UTCEPSS rescore
  5. 2026-08-20 17:07 UTCVendor advisory
  6. 2026-08-20 17:07 UTCGHSA enrichment
  7. 2026-08-20 15:54 UTCVendor advisory
  8. 2026-08-20 15:54 UTCGHSA enrichment
  9. 2026-08-20 04:26 UTCEG score recompute
  10. 2026-08-20 04:26 UTCGHSA enrichment
  11. 2026-08-19 17:04 UTCEPSS rescore
  12. 2026-08-19 16:57 UTCVendor advisory
  13. 2026-08-19 16:57 UTCGHSA enrichment
  14. 2026-08-19 15:49 UTCVendor advisory
  15. 2026-08-19 15:49 UTCGHSA enrichment
  16. 2026-08-19 05:10 UTCVendor advisory
  17. 2026-08-19 05:10 UTCGHSA enrichment
  18. 2026-08-18 17:33 UTCVendor advisory
  19. 2026-08-18 17:33 UTCGHSA enrichment
  20. 2026-08-18 16:00 UTCEG score recompute
  21. 2026-08-18 16:00 UTCVendor advisory
  22. 2026-08-18 16:00 UTCGHSA enrichment
  23. 2026-08-18 13:48 UTCEPSS rescore
  24. 2026-08-18 05:53 UTCGHSA enrichment
  25. 2026-08-17 18:25 UTCVendor advisory
Show 75 more
  1. 2026-08-17 18:25 UTCGHSA enrichment
  2. 2026-08-17 14:26 UTCGHSA enrichment
  3. 2026-08-17 02:58 UTCVendor advisory
  4. 2026-08-17 02:58 UTCGHSA enrichment
  5. 2026-08-16 15:29 UTCEG score recompute
  6. 2026-08-16 15:29 UTCVendor advisory
  7. 2026-08-16 15:29 UTCGHSA enrichment
  8. 2026-08-16 14:56 UTCEPSS rescore
  9. 2026-08-16 04:01 UTCEG score recompute
  10. 2026-08-16 04:01 UTCVendor advisory
  11. 2026-08-16 04:01 UTCGHSA enrichment
  12. 2026-08-15 16:33 UTCVendor advisory
  13. 2026-08-15 16:33 UTCGHSA enrichment
  14. 2026-08-15 05:05 UTCEG score recompute
  15. 2026-08-15 05:05 UTCVendor advisory
  16. 2026-08-15 05:05 UTCGHSA enrichment
  17. 2026-08-15 01:30 UTCEPSS rescore
  18. 2026-08-14 17:36 UTCVendor advisory
  19. 2026-08-14 17:36 UTCGHSA enrichment
  20. 2026-08-14 17:11 UTCVendor advisory
  21. 2026-08-14 17:11 UTCGHSA enrichment
  22. 2026-08-14 13:23 UTCVendor advisory
  23. 2026-08-14 13:23 UTCGHSA enrichment
  24. 2026-08-14 01:54 UTCEG score recompute
  25. 2026-08-14 01:54 UTCVendor advisory
  26. 2026-08-14 01:54 UTCGHSA enrichment
  27. 2026-08-13 22:00 UTCEPSS rescore
  28. 2026-08-13 14:26 UTCVendor advisory
  29. 2026-08-13 14:26 UTCGHSA enrichment
  30. 2026-08-13 02:57 UTCGHSA enrichment
  31. 2026-08-12 15:29 UTCEG score recompute
  32. 2026-08-12 15:29 UTCVendor advisory
  33. 2026-08-12 15:29 UTCGHSA enrichment
  34. 2026-08-12 13:51 UTCEPSS rescore
  35. 2026-08-12 04:01 UTCVendor advisory
  36. 2026-08-12 04:01 UTCGHSA enrichment
  37. 2026-08-11 16:33 UTCEG score recompute
  38. 2026-08-11 16:33 UTCVendor advisory
  39. 2026-08-11 16:33 UTCGHSA enrichment
  40. 2026-08-11 05:04 UTCEG score recompute
  41. 2026-08-11 05:04 UTCVendor advisory
  42. 2026-08-11 05:04 UTCGHSA enrichment
  43. 2026-08-11 00:00 UTCEPSS rescore
  44. 2026-08-10 17:35 UTCGHSA enrichment
  45. 2026-08-10 15:19 UTCGHSA enrichment
  46. 2026-08-10 03:50 UTCGHSA enrichment
  47. 2026-08-09 16:22 UTCEG score recompute
  48. 2026-08-09 16:22 UTCGHSA enrichment
  49. 2026-08-09 13:47 UTCEPSS rescore
  50. 2026-08-09 04:54 UTCGHSA enrichment
  51. 2026-08-08 17:26 UTCEG score recompute
  52. 2026-08-08 17:26 UTCVendor advisory
  53. 2026-08-08 17:26 UTCGHSA enrichment
  54. 2026-08-08 16:37 UTCEPSS rescore
  55. 2026-08-08 05:57 UTCGHSA enrichment
  56. 2026-08-07 18:29 UTCEG score recompute
  57. 2026-08-07 18:29 UTCGHSA enrichment
  58. 2026-08-07 09:54 UTCVendor advisory
  59. 2026-08-07 09:54 UTCGHSA enrichment
  60. 2026-08-06 22:25 UTCVendor advisory
  61. 2026-08-06 22:25 UTCGHSA enrichment
  62. 2026-08-06 17:17 UTCEG score recompute▲ 2.30
  63. 2026-08-06 17:17 UTCVendor advisory
  64. 2026-08-06 17:16 UTCGHSA enrichment
  65. 2026-08-06 17:15 UTCNVD updateCVSS v3 → 8.8 · severity → HIGH
  66. 2026-08-06 15:50 UTCEG score recompute
  67. 2026-08-06 15:50 UTCVendor advisory
  68. 2026-08-06 15:50 UTCGHSA enrichment
  69. 2026-08-06 13:47 UTCEPSS rescore
  70. 2026-08-05 19:17 UTCEPSS rescore
  71. 2026-08-05 19:17 UTCEPSS rescore
  72. 2026-08-05 14:28 UTCEG score recompute
  73. 2026-08-05 14:28 UTCVendor advisory
  74. 2026-08-05 14:28 UTCGHSA enrichment
  75. 2026-08-05 13:49 UTCEG score recompute

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 August 20, 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 36.9% 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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