This vulnerability (CVE-2026-20857) is classified as CWE-822: Untrusted Pointer Dereference. It affects the Windows Cloud Files Mini Filter Driver in Windows 10 Version 1809 (build 10.0.17763.0). An authorized local attacker can exploit this flaw to elevate privileges on the affected system. The CVSS 3.1 vector indicates the attack requires local access with low complexity and no user interaction, and successful exploitation results in high impact on confidentiality, integrity, and availability. The vulnerability is publicly disclosed and a patch is available from Microsoft.

Successful exploitation allows an authorized local attacker to elevate privileges, potentially gaining higher system rights than intended. This can lead to full system compromise, including unauthorized access to sensitive data and disruption of system operations. The vulnerability affects confidentiality, integrity, and availability at a high level.

A patch is available from Microsoft to remediate this vulnerability. It is recommended to apply the official update for Windows 10 Version 1809 as soon as possible to mitigate the risk. Since this is not a cloud service, remediation depends on applying the patch to affected systems. There are no known exploits in the wild, but timely patching is advised.