CVE-2026-45657

CRITICALPre-NVD 9.89.8—
EchelonGraph scoreMEDIUM confidence

Score 9.8 from GitHub Security Advisory (severity: CRITICAL) published 2026-06-09. the CNA's CVSS baseline 9.8; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: cna:microsoft, epss, ghsa
Trending — 4 sources updated this weekElevated
9.8EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 15%CVSS: 9.8Exploit: Elevated riskExposed: 0

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

Use after free in Windows Kernel allows an unauthorized attacker to execute code over a network.

CVSS v3
9.8
EG Score
9.8(medium)
EG Risk
75(Track)
EG Risk 75/100SSVC: 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%
Exploitation40% × 40%
Automatability100% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
15%
EPSS %ILE
97%
KEV
Not listed

Published

June 9, 2026

Last Modified

August 25, 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-2026-45657

Vendor Advisories for CVE-2026-45657(2)

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

Weakness Classification(2)

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

Data Freshness Timeline

(refreshed 11× in last 7d / 71× 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 660 total refreshes for this CVE.

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

Frequently asked(5)

What is CVE-2026-45657?
CVE-2026-45657 is a critical vulnerability published on June 9, 2026. Use after free in Windows Kernel allows an unauthorized attacker to execute code over a network.
When was CVE-2026-45657 disclosed?
CVE-2026-45657 was first published in the National Vulnerability Database on June 9, 2026, with the most recent update on August 25, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-45657 actively exploited?
CVE-2026-45657 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 15% probability of exploitation in the next 30 days, which ranks it in the top 3.4% of all scored CVEs.
What is the CVSS score of CVE-2026-45657?
CVE-2026-45657 has a CVSS v4.0 base score of 9.8 (CNA self-assessment; NVD's own analysis pending).
How do I remediate CVE-2026-45657?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-45657, 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

Explore the affected products and dependency analysis for CVE-2026-45657

Explore →

Is Your Infrastructure Affected by CVE-2026-45657?

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

Start Free Scan →Browse All CVEs