CVE-2026-34344

HIGHNVD 7.87.8—

7.8

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(high)
EPSS: 31.3%
KEV: Not listed

Published

May 12, 2026

Last Modified

May 14, 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.

CVE-2026-34344
Microsoft Security Response Center (MSRC)Elevation of Privilege
Windows Ancillary Function Driver for WinSock Elevation of Privilege Vulnerability

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 May 14, 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 31.3% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.

What is the CVSS score of CVE-2026-34344?

CVE-2026-34344 has a CVSS v3 base score of 7.8 (NVD).

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.

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CVE-2026-34344

📅 Published

🔄 Last Modified

📋 Advisory Details (1)

Security Update Guide - Microsoft Security Response Center

📣 Vendor Advisories for CVE-2026-34344(1)

❓ Frequently asked(5)