CVE-2026-42915

MEDIUMPre-NVD 5.55.7▲
EchelonGraph scoreMEDIUM 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
5.7EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0.4%CVSS: 5.5Exploit: None knownExposed services: Not assessed

A fix is referenced (a reference tagged "Patch", often a source commit), but no release containing it is confirmed — find the release that contains it; until it is applied, mitigate (WAF / firewall / segmentation).

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

CVSS v3
5.5
EG Score
5.7MEDIUMmedium confidence
EG Risk
26
EG Risk 26/100

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
Severity57% × 45%
Exploitation0% × 40%
Automatability0% × 15%
EPSS PROB
0.4%
EPSS %ILE
32nd
KEV
Not listed

Published

June 9, 2026

Last Modified

September 24, 2026

Advisory Details (1)

Auto-updated Jun 13, 2026
Fix referenced — no release confirmed yet. Sources: microsoft.
microsoftMentions a patch (unverified)

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 7× in last 7d / 27× 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 275 total refreshes for this CVE.

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

Related CVEs(same CWE)

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 on June 9, 2026, with the most recent update on September 24, 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 0.4% probability of exploitation in the next 30 days (32nd percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-42915?
CVE-2026-42915 has a CVSS base score of 5.5 (the CNA's own assessment, by microsoft; NVD's own analysis pending). EchelonGraph synthesises NVD + CISA KEV + FIRST EPSS + GHSA into a combined EG score of 5.7 (MEDIUM).
How do I remediate CVE-2026-42915?
A fix for CVE-2026-42915 is referenced (a reference tagged "Patch", often a source commit), but EchelonGraph has no release containing it on record. Check that reference and the vendor's advisory for a release that contains the fix and update to it; until then, restrict network exposure of the affected system or apply the vendor's mitigation. The vendor advisories EchelonGraph has for CVE-2026-42915 are linked in the Vendor Advisories panel on this page.

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.

Book a Demo →Browse All CVEs