CVE-2025-62221MicrosoftOperating systemsDecember 9, 2025

Microsoft Windows Use After Free Vulnerability

High 7.8Actively exploited

Description

Microsoft Windows Cloud Files Mini Filter Driver contains a use after free vulnerability that can allow an authorized attacker to elevate privileges locally.

What to do

Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

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Details

Vendor
Microsoft
Product
Windows
CVE
CVE-2025-62221
Affected versions
Windows 10 Version 1809 10.0: from 10.0.17763.0 to 10.0.17763.8146 (excluded) — fixed in 10.0.17763.8146
Windows 10 Version 21H2 10.0: from 10.0.19044.0 to 10.0.19044.6691 (excluded) — fixed in 10.0.19044.6691
Windows 10 Version 22H2 10.0: from 10.0.19045.0 to 10.0.19045.6691 (excluded) — fixed in 10.0.19045.6691
Windows 11 version 22H3 10.0: from 10.0.22631.0 to 10.0.22631.6345 (excluded) — fixed in 10.0.22631.6345
Windows 11 Version 23H2 10.0: from 10.0.22631.0 to 10.0.22631.6345 (excluded) — fixed in 10.0.22631.6345
Windows 11 Version 24H2 10.0: from 10.0.26100.0 to 10.0.26100.7462 (excluded) — fixed in 10.0.26100.7462
Windows 11 Version 25H2 10.0: from 10.0.26200.0 to 10.0.26200.7462 (excluded) — fixed in 10.0.26200.7462
Windows Server 2019 10.0: from 10.0.17763.0 to 10.0.17763.8146 (excluded) — fixed in 10.0.17763.8146
Windows Server 2019 (Server Core installation) 10.0: from 10.0.17763.0 to 10.0.17763.8146 (excluded) — fixed in 10.0.17763.8146
Windows Server 2022 10.0: from 10.0.20348.0 to 10.0.20348.4529 (excluded) — fixed in 10.0.20348.4529
Windows Server 2022, 23H2 Edition (Server Core installation) 10.0: from 10.0.25398.0 to 10.0.25398.2025 (excluded) — fixed in 10.0.25398.2025
Windows Server 2025 10.0: from 10.0.26100.0 to 10.0.26100.7462 (excluded) — fixed in 10.0.26100.7462
Windows Server 2025 (Server Core installation) 10.0: from 10.0.26100.0 to 10.0.26100.7462 (excluded) — fixed in 10.0.26100.7462 (from the advisory and NVD; check the exact builds in the official advisory)
CVSS score
7.8
Actively exploited
Yes, listed in the CISA Known Exploited Vulnerabilities catalog
CISA due date
December 30, 2025 (deadline for US federal agencies: a good benchmark for you too)
Source
CISA KEV – original advisory
Published
December 9, 2025

The description and the recommended action are quoted from the public advisory; severity, exploitation status and affected versions are compiled automatically from public sources and may contain errors. The vendor's original advisory prevails: check it before taking action. This information is provided without warranty and does not replace a professional assessment.

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