CVE-2026-62815

CRITICALPre-NVD 9.89.8—
EchelonGraph scoreMEDIUM confidence

Score 9.8 from GitHub Security Advisory (severity: CRITICAL) published 2026-08-11. the CNA's CVSS baseline 9.8; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: cna:microsoft, epss, ghsa
Trending — 3 sources updated this week
9.8EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 1%CVSS: 9.8Exploit: None knownExposed: 0

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

Use after free in Microsoft QUIC allows an unauthorized attacker to execute code over a network.

CVSS v3
9.8
EG Score
9.8(medium)
EG Risk
60(Track)
EG Risk 60/100SSVC: 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
Severity98% × 45%
Exploitation1% × 40%
Automatability100% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
1%
EPSS %ILE
68%
KEV
Not listed

Published

August 11, 2026

Last Modified

September 16, 2026

Advisory Details (1)

Auto-updated Sep 16, 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-2026-62815

Vendor Advisories for CVE-2026-62815(2)

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

Affected Packages

(2 across 1 ecosystem)
NuGet(2)
PackageVulnerable rangeFixed inDependents
Microsoft.Native.Quic.MsQuic.OpenSSL1.8.02.4.19—
Microsoft.Native.Quic.MsQuic.Schannel1.8.02.4.19—

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 42× in last 7d / 283× 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 477 total refreshes for this CVE.

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

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-62815?
CVE-2026-62815 is a critical vulnerability published on August 11, 2026. Use after free in Microsoft QUIC allows an unauthorized attacker to execute code over a network.
When was CVE-2026-62815 disclosed?
CVE-2026-62815 was first published in the National Vulnerability Database on August 11, 2026, with the most recent update on September 16, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-62815 actively exploited?
CVE-2026-62815 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 32.3% of all scored CVEs.
What is the CVSS score of CVE-2026-62815?
CVE-2026-62815 has a CVSS v4.0 base score of 9.8 (CNA self-assessment; NVD's own analysis pending).
How do I remediate CVE-2026-62815?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-62815, 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

See which npm, PyPI, Go, and Maven packages are affected by CVE-2026-62815

Explore →

Is Your Infrastructure Affected by CVE-2026-62815?

EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.

Start Free Scan →Browse All CVEs