EUVD-2026-44312
GHSA-fq9x-x87x-q852
Severity by source
AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Local privilege escalation from an authenticated low-priv user (AV:L, PR:L) via a reliable use-after-free (AC:L) yielding SYSTEM-level full C/I/A impact.
Primary rating from Vendor (microsoft).
CVSS VectorVendor: microsoft
Lifecycle Timeline
2DescriptionCVE.org
Use after free in Desktop Window Manager allows an authorized attacker to elevate privileges locally.
AnalysisAI
Local privilege escalation in the Desktop Window Manager (DWM) component of Windows 11 version 26H1 allows an authenticated local attacker to elevate to SYSTEM by triggering a use-after-free memory corruption condition. The CVSS 3.1 vector (AV:L/PR:L) confirms an already-authenticated low-privileged user is required, and full compromise of confidentiality, integrity, and availability follows successful exploitation. Microsoft has released a patch; there is no public exploit identified at time of analysis and the flaw is not listed in CISA KEV.
Technical ContextAI
The vulnerability resides in the Desktop Window Manager (dwm.exe / underlying compositor libraries), the Windows compositing engine that manages window rendering, visual effects, and per-application graphics buffers, and which runs with elevated privileges as part of the desktop session. The root cause is CWE-416 (Use After Free): the DWM code continues to reference a memory object after it has been freed, so an attacker who can control reallocation of that freed memory can influence a dangling pointer to hijack execution flow or corrupt privileged data structures. The affected CPE is cpe:2.3:a:microsoft:windows_11_version_26h1, identifying Windows 11 version 26H1 as the impacted product line.
RemediationAI
Patch available per vendor advisory - apply the Microsoft security update for CVE-2026-58633 published in the MSRC update guide at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-58633, which supplies the fixed cumulative update for Windows 11 version 26H1 (consult the advisory for the exact KB and build number, which are not reproduced in the input data). Because exploitation requires an existing local foothold, in the interim before patching you should limit local logon and interactive access to the affected hosts, enforce least-privilege so fewer standard users can run arbitrary code, and monitor for anomalous processes interacting with dwm.exe; note these are only risk-reducing compensating controls and do not remove the underlying use-after-free, so patching remains the sole complete fix.
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Same weakness CWE-416 – Use After Free
View allSame technique Use After Free
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External POC / Exploit Code
Leaving vuln.today