CVE-2026-21519highunder attackCWE-843

CVE-2026-21519: high-severity vulnerability in Microsoft Windows 10 Version 1607

Desktop Window Manager Elevation of Privilege Vulnerability

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51Vexday Risk Score

Prioritize patching. It under exploitation confirmed by CISA and has an official Brazilian government alert.

ssvc Actcvss 7.8epss 2.5%
from disclosure to weapon
Published on NVDFeb 10
CISA KEVFeb 10
Official alert in Brazil

Brazil's federal government published an alert, recommendation or bulletin that cites this vulnerability.

Source: CTIR Gov (GSI) and CISC Gov.br, under the CC BY-ND 3.0 license.
Action required by CISAfederal deadline: 2026-03-03

Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

In short

A flaw in Windows Desktop Window Manager allows an authorized user to gain higher system privileges through type confusion, where the system mishandles data types in memory.

Technical detail

Type confusion vulnerability (CWE-843) in Desktop Window Manager permits local privilege escalation by an authenticated attacker exploiting incompatible type access; requires prior system access and results in elevated privileges.

Summary generated and translated by AI from the official description.

The full analysis of this CVE is available in Portuguese →

Access of resource using incompatible type ('type confusion') in Desktop Window Manager allows an authorized attacker to elevate privileges locally.
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C
Affected products
Microsoft · Windows 10 Version 1607Microsoft · Windows 10 Version 1809Microsoft · Windows 10 Version 21H2Microsoft · Windows 10 Version 22H2Microsoft · Windows 11 version 22H3Microsoft · Windows 11 Version 23H2Microsoft · Windows 11 Version 24H2Microsoft · Windows 11 Version 25H2Microsoft · Windows 11 version 26H1Microsoft · Windows Server 2016Microsoft · Windows Server 2016 (Server Core installation)Microsoft · Windows Server 2019Microsoft · Windows Server 2019 (Server Core installation)Microsoft · Windows Server 2022Microsoft · Windows Server 2022, 23H2 Edition (Server Core installation)Microsoft · Windows Server 2025Microsoft · Windows Server 2025 (Server Core installation)
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