CVE-2026-42915

MEDIUMPre-NVD 5.55.7▲
EchelonGraph scoreHIGH confidence

Score 5.7 from GitHub Security Advisory published 2026-06-09. the CNA's CVSS baseline 5.5; sources differ by 0.2.

Triggered by: GitHub Security Advisory CVSS
Sources: cna:microsoft, epss, ghsa
Trending — 4 sources updated this week
5.5
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS: 0%CVSS: 5.5Exploit: NoneExposed: 0

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

Incorrect calculation of buffer size in Windows VMSwitch allows an authorized attacker to deny service locally.

CVSS v3
5.5
EG Score
5.7(high)
EPSS
30.3%
KEV
Not listed

Published

June 9, 2026

Last Modified

July 1, 2026

Advisory Details (1)

Auto-updated Jun 13, 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-2026-42915

Vendor Advisories for CVE-2026-42915(2)

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 25× in last 7d / 110× 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 110 total refreshes for this CVE.

  1. 2026-07-06 16:27 UTCEPSS rescore
  2. 2026-07-06 16:27 UTCEPSS rescore
  3. 2026-07-06 02:23 UTCEPSS rescore
  4. 2026-07-06 02:23 UTCEPSS rescore
  5. 2026-07-05 13:35 UTCEG score recompute
  6. 2026-07-05 13:35 UTCVendor advisory
  7. 2026-07-05 13:35 UTCGHSA enrichment
  8. 2026-07-04 13:30 UTCEG score recompute
  9. 2026-07-04 13:30 UTCVendor advisory
  10. 2026-07-04 13:29 UTCGHSA enrichment
  11. 2026-07-04 06:31 UTCEPSS rescore
  12. 2026-07-03 08:48 UTCEG score recompute
  13. 2026-07-03 08:48 UTCVendor advisory
  14. 2026-07-03 08:48 UTCGHSA enrichment
  15. 2026-07-02 06:56 UTCEG score recompute
  16. 2026-07-02 06:56 UTCVendor advisory
  17. 2026-07-02 06:55 UTCGHSA enrichment
  18. 2026-07-01 15:06 UTCEPSS rescore
  19. 2026-07-01 07:52 UTCEG score recompute
  20. 2026-07-01 07:52 UTCVendor advisory
  21. 2026-07-01 07:52 UTCGHSA enrichment
  22. 2026-06-30 23:22 UTCEPSS rescore
  23. 2026-06-30 08:50 UTCEG score recompute
  24. 2026-06-30 08:50 UTCVendor advisory
  25. 2026-06-30 08:49 UTCGHSA enrichment
Show 75 more
  1. 2026-06-29 09:47 UTCEG score recompute
  2. 2026-06-29 09:47 UTCVendor advisory
  3. 2026-06-29 09:47 UTCGHSA enrichment
  4. 2026-06-28 14:07 UTCEPSS rescore
  5. 2026-06-28 10:42 UTCEG score recompute
  6. 2026-06-28 10:42 UTCVendor advisory
  7. 2026-06-28 10:41 UTCGHSA enrichment
  8. 2026-06-28 04:56 UTCEPSS rescore
  9. 2026-06-27 11:37 UTCEG score recompute
  10. 2026-06-27 11:37 UTCVendor advisory
  11. 2026-06-27 11:37 UTCGHSA enrichment
  12. 2026-06-27 03:08 UTCEPSS rescore
  13. 2026-06-26 12:34 UTCEG score recompute
  14. 2026-06-26 12:34 UTCVendor advisory
  15. 2026-06-26 12:34 UTCGHSA enrichment
  16. 2026-06-25 13:49 UTCEPSS rescore
  17. 2026-06-25 13:49 UTCEPSS rescore
  18. 2026-06-25 08:13 UTCEG score recompute
  19. 2026-06-25 08:13 UTCVendor advisory
  20. 2026-06-25 08:13 UTCGHSA enrichment
  21. 2026-06-24 14:05 UTCEPSS rescore
  22. 2026-06-24 09:09 UTCEG score recompute
  23. 2026-06-24 09:09 UTCVendor advisory
  24. 2026-06-24 09:09 UTCGHSA enrichment
  25. 2026-06-23 21:33 UTCEPSS rescore
  26. 2026-06-23 10:06 UTCEG score recompute
  27. 2026-06-23 10:06 UTCVendor advisory
  28. 2026-06-23 10:06 UTCGHSA enrichment
  29. 2026-06-22 14:25 UTCEPSS rescore
  30. 2026-06-22 14:25 UTCEPSS rescore
  31. 2026-06-22 09:11 UTCEG score recompute
  32. 2026-06-22 09:11 UTCVendor advisory
  33. 2026-06-22 09:11 UTCGHSA enrichment
  34. 2026-06-21 14:56 UTCEPSS rescore
  35. 2026-06-21 14:56 UTCEPSS rescore
  36. 2026-06-21 07:45 UTCEG score recompute
  37. 2026-06-21 07:45 UTCVendor advisory
  38. 2026-06-21 07:45 UTCGHSA enrichment
  39. 2026-06-21 01:59 UTCEPSS rescore
  40. 2026-06-20 08:40 UTCEG score recompute
  41. 2026-06-20 08:40 UTCVendor advisory
  42. 2026-06-20 08:40 UTCGHSA enrichment
  43. 2026-06-19 21:37 UTCNVD updateCVSS v3 → 5.5
  44. 2026-06-19 19:25 UTCEPSS rescore
  45. 2026-06-19 09:36 UTCEG score recompute
  46. 2026-06-19 09:36 UTCVendor advisory
  47. 2026-06-19 09:36 UTCGHSA enrichment
  48. 2026-06-18 17:52 UTCEPSS rescore
  49. 2026-06-18 17:52 UTCEPSS rescore
  50. 2026-06-18 09:38 UTCEG score recompute
  51. 2026-06-18 09:38 UTCVendor advisory
  52. 2026-06-18 09:38 UTCGHSA enrichment
  53. 2026-06-17 17:53 UTCEPSS rescore
  54. 2026-06-17 09:57 UTCEG score recompute
  55. 2026-06-17 09:57 UTCGHSA enrichment
  56. 2026-06-16 17:52 UTCEPSS rescore
  57. 2026-06-16 10:55 UTCEG score recompute
  58. 2026-06-16 10:55 UTCVendor advisory
  59. 2026-06-16 10:55 UTCGHSA enrichment
  60. 2026-06-15 17:49 UTCEPSS rescore
  61. 2026-06-15 11:53 UTCEG score recompute
  62. 2026-06-15 11:53 UTCVendor advisory
  63. 2026-06-15 11:52 UTCGHSA enrichment
  64. 2026-06-14 12:35 UTCEG score recompute
  65. 2026-06-14 12:35 UTCVendor advisory
  66. 2026-06-14 12:35 UTCGHSA enrichment
  67. 2026-06-13 23:00 UTCEPSS rescore
  68. 2026-06-13 13:33 UTCEG score recompute
  69. 2026-06-13 13:33 UTCGHSA enrichment
  70. 2026-06-12 23:12 UTCEPSS rescore
  71. 2026-06-12 23:12 UTCEPSS rescore
  72. 2026-06-12 14:28 UTCEG score recompute
  73. 2026-06-12 14:28 UTCVendor advisory
  74. 2026-06-12 14:28 UTCGHSA enrichment
  75. 2026-06-11 15:25 UTCEG score recompute

Frequently asked(5)

What is CVE-2026-42915?
CVE-2026-42915 is a medium vulnerability published on June 9, 2026. Incorrect calculation of buffer size in Windows VMSwitch allows an authorized attacker to deny service locally.
When was CVE-2026-42915 disclosed?
CVE-2026-42915 was first published in the National Vulnerability Database on June 9, 2026, with the most recent update on July 1, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-42915 actively exploited?
CVE-2026-42915 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 30.3% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-42915?
CVE-2026-42915 has a CVSS v4.0 base score of 5.5 (CNA self-assessment; NVD's own analysis pending). EchelonGraph synthesises NVD + CISA KEV + FIRST EPSS + GHSA into a combined EG score of 5.7.
How do I remediate CVE-2026-42915?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-42915, 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-2026-42915

Explore →

Is Your Infrastructure Affected by CVE-2026-42915?

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

Start Free Scan →Browse All CVEs