CVE-2026-42978

HIGHPre-NVD 7.87.8—
EchelonGraph scoreMEDIUM confidence

Score 7.8 from GitHub Security Advisory (severity: HIGH) published 2026-06-09. the CNA's CVSS baseline 7.8; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: cna:microsoft, epss, ghsa
Trending — 4 sources updated this weekElevated
7.8EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 7.8Exploit: Elevated riskExposed: 0

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

Concurrent execution using shared resource with improper synchronization ('race condition') in Windows Push Notifications allows an authorized attacker to elevate privileges locally.

CVSS v3
7.8
EG Score
7.8(medium)
EG Risk
51(Track)
EG Risk 51/100SSVC: 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
Severity78% × 45%
Exploitation40% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
16%
KEV
Not listed

Published

June 9, 2026

Last Modified

August 25, 2026

Advisory Details (1)

Auto-updated Jun 9, 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-2026-42978

Vendor Advisories for CVE-2026-42978(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 9× in last 7d / 57× 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 361 total refreshes for this CVE.

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

Publicly available exploits

(3 references)

Working exploit code is in the public domain (3 GitHub PoCs). Defenders should treat patch urgency accordingly — public PoCs typically lead to mass-exploitation within 24-72 hours.

  • GitHub PoCSyntaxMethod/CVE-2026-42978-PoC-Research
    First seen Sep 11, 2026

    CVE-2026-42978 Windows Push Notifications (WpnService) Use-After-Free & Race Condition PoC research, diagnostic scanner, and security audit module for AI Security Tool.

    Open source ↗
  • GitHub PoCgrizzzer/CVE-2026-42978-PoC-Research
    First seen Jun 23, 2026

    CVE-2026-42978 — Use-After-Free race condition in Windows Push Notifications (WpnService). Patch diff, root cause analysis, TOCTOU lab, Sysmon/ETW detection rules.

    Open source ↗
  • GitHub PoCZeroDayEvil/CVE-2026-42978-PoC-Research
    First seen Feb 7, 2026
    Open source ↗

Frequently asked(5)

What is CVE-2026-42978?
CVE-2026-42978 is a high vulnerability published on June 9, 2026. Concurrent execution using shared resource with improper synchronization ('race condition') in Windows Push Notifications allows an authorized attacker to elevate privileges locally.
When was CVE-2026-42978 disclosed?
CVE-2026-42978 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-2026-42978 actively exploited?
CVE-2026-42978 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 84.0% of all scored CVEs.
What is the CVSS score of CVE-2026-42978?
CVE-2026-42978 has a CVSS v4.0 base score of 7.8 (CNA self-assessment; NVD's own analysis pending).
How do I remediate CVE-2026-42978?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-42978, 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-2026-42978

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