cve 2026 20940

CVE-2026-20940 is a high-priority elevation-of-privilege vulnerability in the Windows Cloud Files Mini Filter Driver (cldflt.sys). This kernel component handles cloud-backed file operations, and the flaw allows a local attacker to escalate privileges. Microsoft has released security updates to address the issue. Administrators should prioritize patching by identifying the relevant KBs, testing in pilot rings, and deploying fixes to high-value hosts. The vulnerability is documented in Microsoft's Security Update Guide and requires immediate attention to mitigate local escalation risks.