CVE-2026-21241 HIGH

CVE-2026-21241: Windows Ancillary Function Driver for WinSock Elevation of Privilege Vulnerability

Vendor Microsoft
Product Windows 11 version 22H3
Weakness CWE-416
Published February 10, 2026
Last update May 11, 2026

CVSS base score

7.0/10
Attack vector Local
Attack complexity High
Privileges required Low
User interaction None
Confidentiality High
Integrity High

CVSS vector

CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C

What the vulnerability does

01Description

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

Key dates

02Disclosure timeline

February 10, 2026 CVE published
May 11, 2026 Record updated