About Elevation of Privilege – Microsoft DWM Core Library (CVE-2025-30400) vulnerability. The vulnerability, patched as part of May Microsoft Patch Tuesday, affects the Desktop Window Manager component. This is a compositing window manager that has been part of Windows since Windows Vista. Successful exploitation could grant an attacker SYSTEM-level privileges. At the time the vulnerability was disclosed, there were signs of in-the-wild exploitation. No details about the attacks are available yet.
According to the Acknowledgements, exploitation was discovered by the Microsoft Threat Intelligence Center, which rarely shares details. 
We’ll have to wait for reports from other researchers or a public exploit. There is currently one GitHub repository with a PoC, but its functionality is highly questionable. 
The previous actively exploited EoP vulnerability in the DWM Core Library (CVE-2024-30051) was patched in May last year.
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