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
Trending — 4 sources updated this week
5.7EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 5.5Exploit: None knownExposed: 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(medium)
EG Risk
26(Track)
EG Risk 26/100SSVC: 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
Severity57% × 45%
Exploitation0% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
31%
KEV
Not listed

Published

June 9, 2026

Last Modified

August 25, 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 22× in last 7d / 107× 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 233 total refreshes for this CVE.

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

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 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-2026-42915 actively exploited?
CVE-2026-42915 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 69.0% of all scored CVEs.
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

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