CVE-2026-33840 - Vulnerability Details - OpenCVE

Use after free in Windows Win32K - ICOMP allows an authorized attacker to elevate privileges locally.

No CVSS v4.0

Attack Vector Local

Attack Complexity Low

Privileges Required Low

Scope Unchanged

Confidentiality Impact High

Integrity Impact High

Availability Impact High

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

No EPSS score available.

Key SSVC decision points have not yet been added.

Vendors	Products
Microsoft	Windows 11 24h2 Windows 11 25h2 Windows 11 26h1 Windows Server 2025

No data.

No data.

OpenCVE Enrichment is a feature of OpenCVE that uses AI to automatically link vendors and products to CVEs. Learn more on GitHub.

Vendors	Products

References

Link	Providers
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-33840

History

Tue, 12 May 2026 17:30:00 +0000

Type	Values Removed	Values Added
Description		Use after free in Windows Win32K - ICOMP allows an authorized attacker to elevate privileges locally.
Title		Win32k Elevation of Privilege Vulnerability
First Time appeared		Microsoft Microsoft windows 11 24h2 Microsoft windows 11 25h2 Microsoft windows 11 26h1 Microsoft windows Server 2025
Weaknesses		CWE-416
CPEs		cpe:2.3:o:microsoft:windows_11_24H2:::::::arm64:* cpe:2.3:o:microsoft:windows_11_25H2:::::::arm64:* cpe:2.3:o:microsoft:windows_11_26H1:::::::x64:* cpe:2.3:o:microsoft:windows_server_2025::::::::
Vendors & Products		Microsoft Microsoft windows 11 24h2 Microsoft windows 11 25h2 Microsoft windows 11 26h1 Microsoft windows Server 2025
References		https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-33840
Metrics		cvssV3_1 `{'score': 7.8, 'vector': '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'}`

MITRE

Status: PUBLISHED

Assigner: microsoft

Published: 2026-05-12T16:58:19.989Z

Updated: 2026-05-12T17:53:18.073Z

Reserved: 2026-03-24T00:52:01.353Z

Link: CVE-2026-33840

Vulnrichment

No data.

NVD

Status : Received

Published: 2026-05-12T18:17:06.163

Modified: 2026-05-12T18:17:06.163

Link: CVE-2026-33840

Redhat

No data.

OpenCVE Enrichment

Updated: 2026-05-12T19:00:20Z

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