CVE-2026-34344

HIGHPre-NVD 7.87.8—
EchelonGraph scoreMEDIUM confidence

Score 7.8 from GitHub Security Advisory (severity: HIGH) published 2026-05-12. the CNA's CVSS baseline 7.8; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: cna:microsoft, epss, ghsa
Elevated
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.

Access of resource using incompatible type ('type confusion') in Windows Ancillary Function Driver for WinSock allows an authorized attacker to elevate privileges locally.

CVSS v3
7.8
EG Score
7.8(medium)
EG Risk
35(Track)
EG Risk 35/100SSVC: 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%
Exploitation0% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
25%
KEV
Not listed

Published

May 12, 2026

Last Modified

August 10, 2026

Advisory Details (1)

Auto-updated May 12, 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-2026-34344

Vendor Advisories for CVE-2026-34344(1)

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 / 28× 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 283 total refreshes for this CVE.

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

Publicly available exploits

(1 reference)

Working exploit code is in the public domain (1 GitHub PoC). Defenders should treat patch urgency accordingly — public PoCs typically lead to mass-exploitation within 24-72 hours.

  • GitHub PoCnhh9905/CVE-2026-34344
    First seen Aug 13, 2026

    CVE 1-day in afd.sys

    Open source ↗

Frequently asked(5)

What is CVE-2026-34344?
CVE-2026-34344 is a high vulnerability published on May 12, 2026. Access of resource using incompatible type ('type confusion') in Windows Ancillary Function Driver for WinSock allows an authorized attacker to elevate privileges locally.
When was CVE-2026-34344 disclosed?
CVE-2026-34344 was first published in the National Vulnerability Database on May 12, 2026, with the most recent update on August 10, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-34344 actively exploited?
CVE-2026-34344 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 75.4% of all scored CVEs.
What is the CVSS score of CVE-2026-34344?
CVE-2026-34344 has a CVSS v4.0 base score of 7.8 (CNA self-assessment; NVD's own analysis pending).
How do I remediate CVE-2026-34344?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-34344, 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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