# KB5009721: January 2022 security update KB5009721, released January 11, 2022, fixes 1 CVE across 19 products. None of them is reported as exploited. Patch Radar priority: High. - Web page: https://patchblox.com/security/fix/microsoft/kb5009721 - Platform: Microsoft - Released: Jan 11, 2022 - Priority: High (Closes CVE-2022-21911, high severity) - CVEs: 1, exploited: 0, on CISA KEV: 0 - Vendor advisory: https://support.microsoft.com/help/5009721 ## Applies to | Product | Release | Fixed in | |---|---|---| | [Microsoft .NET Framework 3.5 on Windows 8.1 for 32-bit systems](https://patchblox.com/security/data/product/microsoft/microsoft-.net-framework-3.5-on-windows-8.1-for-32-bit-systems.md) | | | | [Microsoft .NET Framework 3.5 on Windows 8.1 for x64-based systems](https://patchblox.com/security/data/product/microsoft/microsoft-.net-framework-3.5-on-windows-8.1-for-x64-based-systems.md) | | | | [Microsoft .NET Framework 3.5 on Windows Server 2012 R2](https://patchblox.com/security/data/product/microsoft/microsoft-.net-framework-3.5-on-windows-server-2012-r2.md) | | | | [Microsoft .NET Framework 3.5 on Windows Server 2012 R2 (Server Core installation)](https://patchblox.com/security/data/product/microsoft/microsoft-.net-framework-3.5-on-windows-server-2012-r2-server-core-installation.md) | | | | [Microsoft .NET Framework 4.5.2 on Windows 8.1 for 32-bit systems](https://patchblox.com/security/data/product/microsoft/microsoft-.net-framework-4.5.2-on-windows-8.1-for-32-bit-systems.md) | | | | [Microsoft .NET Framework 4.5.2 on Windows 8.1 for x64-based systems](https://patchblox.com/security/data/product/microsoft/microsoft-.net-framework-4.5.2-on-windows-8.1-for-x64-based-systems.md) | | | | [Microsoft .NET Framework 4.5.2 on Windows RT 8.1](https://patchblox.com/security/data/product/microsoft/microsoft-.net-framework-4.5.2-on-windows-rt-8.1.md) | | | | [Microsoft .NET Framework 4.5.2 on Windows Server 2012 R2](https://patchblox.com/security/data/product/microsoft/microsoft-.net-framework-4.5.2-on-windows-server-2012-r2.md) | | | | [Microsoft .NET Framework 4.5.2 on Windows Server 2012 R2 (Server Core installation)](https://patchblox.com/security/data/product/microsoft/microsoft-.net-framework-4.5.2-on-windows-server-2012-r2-server-core-installation.md) | | | | [Microsoft .NET Framework 4.6/4.6.1/4.6.2/4.7/4.7.1/4.7.2 on Windows 8.1 for 32-bit systems](https://patchblox.com/security/data/product/microsoft/microsoft-.net-framework-4.6-4.6.1-4.6.2-4.7-4.7.1-4.7.2-on-windows-8.1-for-32-bit-systems.md) | | | | [Microsoft .NET Framework 4.6/4.6.1/4.6.2/4.7/4.7.1/4.7.2 on Windows 8.1 for x64-based systems](https://patchblox.com/security/data/product/microsoft/microsoft-.net-framework-4.6-4.6.1-4.6.2-4.7-4.7.1-4.7.2-on-windows-8.1-for-x64-based-systems.md) | | | | [Microsoft .NET Framework 4.6/4.6.1/4.6.2/4.7/4.7.1/4.7.2 on Windows RT 8.1](https://patchblox.com/security/data/product/microsoft/microsoft-.net-framework-4.6-4.6.1-4.6.2-4.7-4.7.1-4.7.2-on-windows-rt-8.1.md) | | | | [Microsoft .NET Framework 4.6/4.6.1/4.6.2/4.7/4.7.1/4.7.2 on Windows Server 2012 R2](https://patchblox.com/security/data/product/microsoft/microsoft-.net-framework-4.6-4.6.1-4.6.2-4.7-4.7.1-4.7.2-on-windows-server-2012-r2.md) | | | | [Microsoft .NET Framework 4.6/4.6.1/4.6.2/4.7/4.7.1/4.7.2 on Windows Server 2012 R2 (Server Core installation)](https://patchblox.com/security/data/product/microsoft/microsoft-.net-framework-4.6-4.6.1-4.6.2-4.7-4.7.1-4.7.2-on-windows-server-2012-r2-server-core-installation.md) | | | | [Microsoft .NET Framework 4.8 on Windows 8.1 for 32-bit systems](https://patchblox.com/security/data/product/microsoft/microsoft-.net-framework-4.8-on-windows-8.1-for-32-bit-systems.md) | | | | [Microsoft .NET Framework 4.8 on Windows 8.1 for x64-based systems](https://patchblox.com/security/data/product/microsoft/microsoft-.net-framework-4.8-on-windows-8.1-for-x64-based-systems.md) | | | | [Microsoft .NET Framework 4.8 on Windows RT 8.1](https://patchblox.com/security/data/product/microsoft/microsoft-.net-framework-4.8-on-windows-rt-8.1.md) | | | | [Microsoft .NET Framework 4.8 on Windows Server 2012 R2](https://patchblox.com/security/data/product/microsoft/microsoft-.net-framework-4.8-on-windows-server-2012-r2.md) | | | | [Microsoft .NET Framework 4.8 on Windows Server 2012 R2 (Server Core installation)](https://patchblox.com/security/data/product/microsoft/microsoft-.net-framework-4.8-on-windows-server-2012-r2-server-core-installation.md) | | | ## CVEs this fix closes | CVE | Priority | Component | CVSS | EPSS | Exploitation | |---|---|---|---:|---:|---| | [CVE-2022-21911](https://patchblox.com/security/data/cve/CVE-2022-21911.md) | High | .NET Framework | 7.5 | 0.0323 | | --- Data as of 2026-11-07T06:34:28Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo