CVE-2026-34344: Windows Ancillary Function Driver for WinSock Elevation of Privilege Vulnerability
Access of resource using incompatible type ('type confusion') in Windows Ancillary Function Driver for WinSock allows an authorized attacker to elevate privileges locally.
Other sources
Windows Ancillary Function Driver for WinSock Elevation of Privilege Vulnerability
— Microsoft
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 6.3.9600.23181Patch KB5087471 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.14393.9140Patch KB5087537 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.28000.2113Patch KB5089548 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.26100.8457Fixed in 10.0.26100.8390Patch KB5089466 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.25398.2330Patch KB5087541 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.26200.8457Fixed in 10.0.26200.8390Patch KB5089466 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.26100.32860Fixed in 10.0.26100.32772Patch KB5087423 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.22631.7219Patch KB5093998 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.19045.7417Patch KB5094127 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.19044.7291Patch KB5087544 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.20348.5139Fixed in 10.0.20348.5074Patch KB5087424 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.17763.8755Patch KB5087538 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 6.2.9200.26079Patch KB5087470 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.22631.7079Patch KB5087420
Event History
Frequently Asked Questions
What is the severity of CVE-2026-34344?
CVE-2026-34344 has a high severity rating due to its potential to allow an authorized attacker to elevate privileges on affected systems.
How do I fix CVE-2026-34344?
To fix CVE-2026-34344, update your affected Windows operating system using the latest security patches provided by Microsoft.
Which Windows versions are affected by CVE-2026-34344?
CVE-2026-34344 affects multiple versions of Windows including Windows 10, Windows 11, and various Windows Server editions.
What impact does CVE-2026-34344 have on user security?
CVE-2026-34344 allows attackers to gain elevated privileges, potentially compromising user security and system integrity.
Is there a workaround for CVE-2026-34344 until a patch is applied?
There are no recommended workarounds for CVE-2026-34344; users are advised to apply the necessary updates as soon as they are available.