# KB4601887: February 2021 security update

KB4601887, released February 9, 2021, fixes 1 CVE across 6 products. None of them is reported as exploited. Patch Radar priority: High. The product is no longer supported.

- Web page: https://patchblox.com/security/fix/microsoft/kb4601887
- Platform: Microsoft
- Released: Feb 9, 2021
- Priority: High (Closes CVE-2021-24111, high severity)
- CVEs: 1, exploited: 0, on CISA KEV: 0
- Vendor advisory: https://support.microsoft.com/help/4601887

## Applies to

| Product | Release | Fixed in |
|---|---|---|
| [Microsoft .NET Framework 4.7.2 on Windows Server 2019](https://patchblox.com/security/data/product/microsoft/microsoft-.net-framework-4.7.2-on-windows-server-2019-11862-11571.md) |  |  |
| [Microsoft .NET Framework 4.7.2 on Windows Server 2019 (Server Core installation)](https://patchblox.com/security/data/product/microsoft/microsoft-.net-framework-4.7.2-on-windows-server-2019-server-core-installation-11862-11572.md) |  |  |
| [Microsoft .NET Framework 4.8 on Windows 10 Version 1809 for 32-bit Systems](https://patchblox.com/security/data/product/microsoft/microsoft-.net-framework-4.8-on-windows-10-version-1809-for-32-bit-systems.md) |  |  |
| [Microsoft .NET Framework 4.8 on Windows 10 Version 1809 for x64-based Systems](https://patchblox.com/security/data/product/microsoft/microsoft-.net-framework-4.8-on-windows-10-version-1809-for-x64-based-systems.md) |  |  |
| [Microsoft .NET Framework 4.8 on Windows Server 2019](https://patchblox.com/security/data/product/microsoft/microsoft-.net-framework-4.8-on-windows-server-2019.md) |  |  |
| [Microsoft .NET Framework 4.8 on Windows Server 2019 (Server Core installation)](https://patchblox.com/security/data/product/microsoft/microsoft-.net-framework-4.8-on-windows-server-2019-server-core-installation.md) |  |  |

## CVEs this fix closes

| CVE | Priority | Component | CVSS | EPSS | Exploitation |
|---|---|---|---:|---:|---|
| [CVE-2021-24111](https://patchblox.com/security/data/cve/CVE-2021-24111.md) | High | .NET Framework | 7.5 | 0.0384 |  |

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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 Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo