CVE-2026-21241

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

CVSS v3 7.0 HIGH

7.0^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.0 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity HIGH

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21241	Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:microsoft:windows_11_23h2:::::::arm64:*
	cpe:2.3:o:microsoft:windows_11_23h2:::::::x64:*
	cpe:2.3:o:microsoft:windows_11_24h2:::::::arm64:*
	cpe:2.3:o:microsoft:windows_11_24h2:::::::x64:*
	cpe:2.3:o:microsoft:windows_11_25h2:::::::arm64:*
	cpe:2.3:o:microsoft:windows_11_25h2:::::::x64:*
	cpe:2.3:o:microsoft:windows_server_2022::::::::
	cpe:2.3:o:microsoft:windows_server_2022_23h2::::::::
	cpe:2.3:o:microsoft:windows_server_2025::::::::

History

No history.

Information

Published : 2026-02-10 18:16

Updated : 2026-02-11 20:57

NVD link : CVE-2026-21241

Mitre link : CVE-2026-21241

CVE.ORG link : CVE-2026-21241

JSON object : View

Products Affected

microsoft

windows_server_2022
windows_11_24h2
windows_11_23h2
windows_server_2025
windows_11_25h2
windows_server_2022_23h2

CWE

CWE-416

Use After Free

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