# KB5006667: October 2021 cumulative update for Windows 10 1909 KB5006667, released October 12, 2021, fixes 38 CVEs across 3 products. 2 of them are being exploited (CVE-2021-40449); 2 on CISA KEV. Patch Radar priority: Patch now. The product is no longer supported. - Web page: https://patchblox.com/security/fix/microsoft/kb5006667 - Platform: Microsoft - Released: Oct 12, 2021 - Priority: Patch now (Closes CVE-2021-40449, exploited (CISA KEV, ransomware)) - CVEs: 38, exploited: 2, on CISA KEV: 2 - Vendor advisory: https://support.microsoft.com/help/5006667 ## 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) | | 18363.1854 | | [Windows 10 Version 1909 for ARM64-based Systems](https://patchblox.com/security/data/product/microsoft/windows-10-version-1909-for-arm64-based-systems.md) | | 18363.1854 | | [Windows 10 Version 1909 for x64-based Systems](https://patchblox.com/security/data/product/microsoft/windows-10-version-1909-for-x64-based-systems.md) | | 18363.1854 | ## CVEs this fix closes | CVE | Priority | Component | CVSS | EPSS | Exploitation | |---|---|---|---:|---:|---| | [CVE-2021-40449](https://patchblox.com/security/data/cve/CVE-2021-40449.md) | Patch now | Windows Win32K | 7.8 | 0.8194 | CISA KEV, Ransomware | | [CVE-2021-40450](https://patchblox.com/security/data/cve/CVE-2021-40450.md) | Patch now | Windows Win32K | 7.8 | 0.0152 | CISA KEV | | [CVE-2021-36970](https://patchblox.com/security/data/cve/CVE-2021-36970.md) | Urgent | Windows Print Spooler Components | 8.8 | 0.0306 | More likely | | [CVE-2021-40461](https://patchblox.com/security/data/cve/CVE-2021-40461.md) | Urgent | Role: Windows Hyper-V | 8.0 | 0.0136 | | | [CVE-2021-40443](https://patchblox.com/security/data/cve/CVE-2021-40443.md) | Urgent | Windows Common Log File System Driver | 7.8 | 0.0065 | More likely | | [CVE-2021-40466](https://patchblox.com/security/data/cve/CVE-2021-40466.md) | Urgent | Windows Common Log File System Driver | 7.8 | 0.0065 | More likely | | [CVE-2021-40470](https://patchblox.com/security/data/cve/CVE-2021-40470.md) | Urgent | Windows DirectX | 7.8 | 0.0065 | More likely | | [CVE-2021-40467](https://patchblox.com/security/data/cve/CVE-2021-40467.md) | Urgent | Windows Common Log File System Driver | 7.8 | 0.0054 | More likely | | [CVE-2021-36953](https://patchblox.com/security/data/cve/CVE-2021-36953.md) | High | Windows TCP/IP | 7.5 | 0.0505 | | | [CVE-2021-40463](https://patchblox.com/security/data/cve/CVE-2021-40463.md) | High | Windows Network Address Translation (NAT) | 7.7 | 0.0258 | | | [CVE-2021-40462](https://patchblox.com/security/data/cve/CVE-2021-40462.md) | High | Microsoft Windows Codecs Library | 7.8 | 0.0252 | | | [CVE-2021-40465](https://patchblox.com/security/data/cve/CVE-2021-40465.md) | High | Windows Text Shaping | 7.8 | 0.0247 | | | [CVE-2021-40476](https://patchblox.com/security/data/cve/CVE-2021-40476.md) | High | Windows AppContainer | 7.5 | 0.0240 | | | [CVE-2021-41330](https://patchblox.com/security/data/cve/CVE-2021-41330.md) | High | Microsoft Windows Codecs Library | 7.8 | 0.0203 | | | [CVE-2021-41331](https://patchblox.com/security/data/cve/CVE-2021-41331.md) | High | Microsoft Windows Codecs Library | 7.8 | 0.0203 | | | [CVE-2021-41340](https://patchblox.com/security/data/cve/CVE-2021-41340.md) | High | Microsoft Graphics Component | 7.8 | 0.0203 | | | [CVE-2021-41335](https://patchblox.com/security/data/cve/CVE-2021-41335.md) | High | Windows Kernel | 7.8 | 0.0137 | Disclosed | | [CVE-2021-40488](https://patchblox.com/security/data/cve/CVE-2021-40488.md) | High | Windows Storage Spaces Controller | 7.8 | 0.0100 | | | [CVE-2021-26441](https://patchblox.com/security/data/cve/CVE-2021-26441.md) | High | Windows Storage Spaces Controller | 7.8 | 0.0094 | | | [CVE-2021-40478](https://patchblox.com/security/data/cve/CVE-2021-40478.md) | High | Windows Storage Spaces Controller | 7.8 | 0.0084 | | | [CVE-2021-40489](https://patchblox.com/security/data/cve/CVE-2021-40489.md) | High | Windows Storage Spaces Controller | 7.8 | 0.0084 | | | [CVE-2021-41345](https://patchblox.com/security/data/cve/CVE-2021-41345.md) | High | Windows Storage Spaces Controller | 7.8 | 0.0083 | | | [CVE-2021-26442](https://patchblox.com/security/data/cve/CVE-2021-26442.md) | High | Windows HTTP.sys | 7.0 | 0.0079 | | | [CVE-2021-41347](https://patchblox.com/security/data/cve/CVE-2021-41347.md) | High | Windows AppX Deployment Service | 7.8 | 0.0071 | | | [CVE-2021-40477](https://patchblox.com/security/data/cve/CVE-2021-40477.md) | High | Windows Event Tracing | 7.8 | 0.0058 | | | [CVE-2021-40464](https://patchblox.com/security/data/cve/CVE-2021-40464.md) | High | Windows Nearby Sharing | 8.0 | 0.0055 | | | [CVE-2021-41338](https://patchblox.com/security/data/cve/CVE-2021-41338.md) | Routine | Windows AppContainer | 5.5 | 0.0330 | Disclosed | | [CVE-2021-41332](https://patchblox.com/security/data/cve/CVE-2021-41332.md) | Routine | Windows Print Spooler Components | 6.5 | 0.0272 | | | [CVE-2021-41342](https://patchblox.com/security/data/cve/CVE-2021-41342.md) | Routine | Windows MSHTML Platform | 6.8 | 0.0163 | | | [CVE-2021-40460](https://patchblox.com/security/data/cve/CVE-2021-40460.md) | Routine | Windows Remote Procedure Call Runtime | 6.5 | 0.0161 | | | [CVE-2021-38624](https://patchblox.com/security/data/cve/CVE-2021-38624.md) | Routine | Windows Key Storage Provider | 6.5 | 0.0153 | | | [CVE-2021-38662](https://patchblox.com/security/data/cve/CVE-2021-38662.md) | Routine | Windows Fast FAT Driver | 5.5 | 0.0078 | | | [CVE-2021-38663](https://patchblox.com/security/data/cve/CVE-2021-38663.md) | Routine | Windows exFAT File System | 5.5 | 0.0073 | | | [CVE-2021-40475](https://patchblox.com/security/data/cve/CVE-2021-40475.md) | Routine | Windows Cloud Files Mini Filter Driver | 5.5 | 0.0073 | | | [CVE-2021-41343](https://patchblox.com/security/data/cve/CVE-2021-41343.md) | Routine | Windows Fast FAT Driver | 5.5 | 0.0073 | | | [CVE-2021-40455](https://patchblox.com/security/data/cve/CVE-2021-40455.md) | Routine | Windows Installer | 5.5 | 0.0056 | | | [CVE-2021-40454](https://patchblox.com/security/data/cve/CVE-2021-40454.md) | Routine | Rich Text Edit Control | 5.5 | 0.0050 | | | [CVE-2021-41339](https://patchblox.com/security/data/cve/CVE-2021-41339.md) | Routine | Windows DWM Core Library | 4.7 | 0.0046 | | --- Data as of 2026-11-09T01:18:40Z UTC. 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