CVE-2026-20811

Access of resource using incompatible type ('type confusion') in Windows Win32K - ICOMP allows an authorized attacker to elevate privileges locally.

CVSS v3 7.8 HIGH

7.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity LOW

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-2026-20811	Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:microsoft:windows_11_23h2::::::::
	cpe:2.3:o:microsoft:windows_11_24h2::::::::
	cpe:2.3:o:microsoft:windows_11_25h2::::::::
	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

17 Jun 2026, 10:17

Type	Values Removed	Values Added
Summary		(es) Acceso a recurso usando tipo incompatible ('confusión de tipos') en Windows Win32K - ICOMP permite a un atacante autorizado elevar privilegios localmente.

14 Jan 2026, 20:13

Type	Values Removed	Values Added
First Time		Microsoft windows Server 2022 Microsoft Microsoft windows 11 23h2 Microsoft windows 11 24h2 Microsoft windows 11 25h2 Microsoft windows Server 2025 Microsoft windows Server 2022 23h2
References	~~() https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-20811 -~~	() https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-20811 - Vendor Advisory
CPE		cpe:2.3:o:microsoft:windows_server_2025:::::::: cpe:2.3:o:microsoft:windows_11_23h2:::::::: cpe:2.3:o:microsoft:windows_server_2022:::::::: cpe:2.3:o:microsoft:windows_11_25h2:::::::: cpe:2.3:o:microsoft:windows_server_2022_23h2:::::::: cpe:2.3:o:microsoft:windows_11_24h2::::::::

13 Jan 2026, 18:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-01-13 18:16

Updated : 2026-07-30 21:16

NVD link : CVE-2026-20811

Mitre link : CVE-2026-20811

CVE.ORG link : CVE-2026-20811

JSON object : View

Products Affected

microsoft

windows_11_25h2
windows_11_24h2
windows_server_2022_23h2
windows_11_23h2
windows_server_2022
windows_server_2025

CWE

CWE-822

Untrusted Pointer Dereference

CWE-843

Access of Resource Using Incompatible Type ('Type Confusion')

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