CVE-2026-21241

HIGH

Windows Ancillary Function Driver for WinSock - Privilege Escalation

Title source: llm
STIX 2.1

Description

Use after free in Windows Ancillary Function Driver for WinSock allows an authorized attacker to elevate privileges locally.

References (1)

Core 1
Core References

Scores

CVSS v3 7.0
EPSS 0.0003
EPSS Percentile 8.9%
Attack Vector LOCAL
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H

CISA SSVC

Vulnrichment
Exploitation none
Automatable no
Technical Impact total

Details

CWE
CWE-416
Status published
Products (16)
Microsoft/Windows 11 version 22H3 10.0.22631.0 - 10.0.22631.6649
Microsoft/Windows 11 Version 23H2 10.0.22631.0 - 10.0.22631.6649
Microsoft/Windows 11 Version 24H2 10.0.26100.0 - 10.0.26100.7840
Microsoft/Windows 11 Version 25H2 10.0.26200.0 - 10.0.26200.7840
Microsoft/Windows 11 version 26H1 10.0.28000.0 - 10.0.28000.1575
Microsoft/Windows 11 Version 26H1 10.0.28000.0 - 10.0.28000.1575
Microsoft/Windows Server 2022 10.0.20348.0 - 10.0.20348.4773
Microsoft/Windows Server 2022, 23H2 Edition (Server Core installation) 10.0.25398.0 - 10.0.25398.2149
Microsoft/Windows Server 2025 10.0.26100.0 - 10.0.26100.32370
Microsoft/Windows Server 2025 (Server Core installation) 10.0.26100.0 - 10.0.26100.32370
... and 6 more
Published Feb 10, 2026
Tracked Since Feb 18, 2026