# KB5008206: December 2021 cumulative update for Windows 10 1909 KB5008206, released December 14, 2021, fixes 30 CVEs across 3 products. One of them is being exploited (CVE-2021-43226); 1 on CISA KEV. Patch Radar priority: Patch now. The product is no longer supported. - Web page: https://patchblox.com/security/fix/microsoft/kb5008206 - Platform: Microsoft - Released: Dec 14, 2021 - Priority: Patch now (Closes CVE-2021-43226, exploited (CISA KEV, ransomware)) - CVEs: 30, exploited: 1, on CISA KEV: 1 - Vendor advisory: https://support.microsoft.com/help/5008206 ## Applies to | Product | Release | Fixed in | |---|---|---| | [Windows 10 Version 1909 for 32-bit Systems](https://patchblox.com/security/data/product/microsoft/windows-10-version-1909-for-32-bit-systems.md) | | 18363.1977 | | [Windows 10 Version 1909 for ARM64-based Systems](https://patchblox.com/security/data/product/microsoft/windows-10-version-1909-for-arm64-based-systems.md) | | 18363.1977 | | [Windows 10 Version 1909 for x64-based Systems](https://patchblox.com/security/data/product/microsoft/windows-10-version-1909-for-x64-based-systems.md) | | 18363.1977 | ## CVEs this fix closes | CVE | Priority | Component | CVSS | EPSS | Exploitation | |---|---|---|---:|---:|---| | [CVE-2021-43226](https://patchblox.com/security/data/cve/CVE-2021-43226.md) | Patch now | Windows Common Log File System Driver | 7.8 | 0.0328 | CISA KEV, Ransomware | | [CVE-2021-43883](https://patchblox.com/security/data/cve/CVE-2021-43883.md) | Urgent | Windows Installer | 7.8 | 0.1215 | Disclosed | | [CVE-2021-43217](https://patchblox.com/security/data/cve/CVE-2021-43217.md) | Urgent | Windows Encrypting File System (EFS) | 8.1 | 0.0652 | | | [CVE-2021-43215](https://patchblox.com/security/data/cve/CVE-2021-43215.md) | Urgent | Internet Storage Name Service | 9.8 | 0.0287 | More likely | | [CVE-2021-43233](https://patchblox.com/security/data/cve/CVE-2021-43233.md) | Urgent | Remote Desktop Client | 7.5 | 0.0236 | More likely | | [CVE-2021-41333](https://patchblox.com/security/data/cve/CVE-2021-41333.md) | Urgent | Windows Print Spooler Components | 7.8 | 0.0108 | Disclosed | | [CVE-2021-43207](https://patchblox.com/security/data/cve/CVE-2021-43207.md) | Urgent | Windows Common Log File System Driver | 7.8 | 0.0068 | More likely | | [CVE-2021-43893](https://patchblox.com/security/data/cve/CVE-2021-43893.md) | High | Windows Encrypting File System (EFS) | 7.5 | 0.0672 | Disclosed | | [CVE-2021-43228](https://patchblox.com/security/data/cve/CVE-2021-43228.md) | High | Windows SymCrypt | 7.5 | 0.0387 | | | [CVE-2021-43219](https://patchblox.com/security/data/cve/CVE-2021-43219.md) | High | Windows DirectX | 7.4 | 0.0387 | | | [CVE-2021-43222](https://patchblox.com/security/data/cve/CVE-2021-43222.md) | High | Windows Message Queuing | 7.5 | 0.0317 | | | [CVE-2021-43236](https://patchblox.com/security/data/cve/CVE-2021-43236.md) | High | Windows Message Queuing | 7.5 | 0.0317 | | | [CVE-2021-43232](https://patchblox.com/security/data/cve/CVE-2021-43232.md) | High | Windows Event Tracing | 7.8 | 0.0218 | | | [CVE-2021-43234](https://patchblox.com/security/data/cve/CVE-2021-43234.md) | High | Role: Windows Fax Service | 7.8 | 0.0218 | | | [CVE-2021-43229](https://patchblox.com/security/data/cve/CVE-2021-43229.md) | High | Windows NTFS | 7.8 | 0.0179 | | | [CVE-2021-43237](https://patchblox.com/security/data/cve/CVE-2021-43237.md) | High | Windows Update Stack | 7.8 | 0.0107 | | | [CVE-2021-43247](https://patchblox.com/security/data/cve/CVE-2021-43247.md) | High | Windows TCP/IP | 7.8 | 0.0092 | | | [CVE-2021-43238](https://patchblox.com/security/data/cve/CVE-2021-43238.md) | High | Windows Remote Access Connection Manager | 7.8 | 0.0091 | | | [CVE-2021-43231](https://patchblox.com/security/data/cve/CVE-2021-43231.md) | High | Windows NTFS | 7.8 | 0.0072 | | | [CVE-2021-43230](https://patchblox.com/security/data/cve/CVE-2021-43230.md) | High | Windows NTFS | 7.8 | 0.0057 | | | [CVE-2021-43240](https://patchblox.com/security/data/cve/CVE-2021-43240.md) | High | Windows NTFS | 7.8 | 0.0057 | Disclosed | | [CVE-2021-43223](https://patchblox.com/security/data/cve/CVE-2021-43223.md) | High | Windows Remote Access Connection Manager | 7.8 | 0.0054 | | | [CVE-2021-43248](https://patchblox.com/security/data/cve/CVE-2021-43248.md) | High | Microsoft Windows Codecs Library | 7.8 | 0.0054 | | | [CVE-2021-43224](https://patchblox.com/security/data/cve/CVE-2021-43224.md) | Routine | Windows Common Log File System Driver | 5.5 | 0.0393 | | | [CVE-2021-43216](https://patchblox.com/security/data/cve/CVE-2021-43216.md) | Routine | Microsoft Local Security Authority Server (lsasrv) | 6.5 | 0.0343 | | | [CVE-2021-24084](https://patchblox.com/security/data/cve/CVE-2021-24084.md) | Routine | Windows Mobile Device Management | 5.5 | 0.0277 | | | [CVE-2021-43244](https://patchblox.com/security/data/cve/CVE-2021-43244.md) | Routine | Windows Kernel | 6.5 | 0.0084 | | | [CVE-2021-43227](https://patchblox.com/security/data/cve/CVE-2021-43227.md) | Routine | Windows Storage Spaces Controller | 5.5 | 0.0079 | | | [CVE-2021-43235](https://patchblox.com/security/data/cve/CVE-2021-43235.md) | Routine | Windows Storage | 5.5 | 0.0079 | | | [CVE-2021-43246](https://patchblox.com/security/data/cve/CVE-2021-43246.md) | Routine | Role: Windows Hyper-V | 5.6 | 0.0077 | | --- Data as of 2026-11-10T07:50:38Z UTC. 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