CVE-2026-65788

Desktop Window Manager is a core Windows component that manages the way windows are drawn on your screen. This flaw is like a timing bug where Windows may use memory it no longer owns, which can let a local attacker turn a limited foothold into higher privileges. The risk is strongest when someone can already run code or interact on the machine.

This matters if you use or manage Windows 11 or Windows Server 2025 on computers that employees, contractors, or external parties can reach. The weakness is a local privilege escalation, so it’s mainly a risk when an attacker already has some way to run on the machine (for example, an account or other local access). It is not described as an internet-facing, no-access-needed flaw.

This is urgent because it’s a serious local privilege escalation bug affecting core Windows functionality, and Microsoft has already released fixes. Even though no KEV listing is present and there’s no public exploit code on record, the issue has received new attention tied to the patch and is associated with advanced threat activity, so you should treat it as a priority update.