# KB4535101: January 2020 security update

KB4535101, released January 14, 2020, fixes 2 CVEs across 8 products. One of them is being exploited (CVE-2020-0646); 1 on CISA KEV. Patch Radar priority: Patch now.

- Web page: https://patchblox.com/security/fix/microsoft/kb4535101
- Platform: Microsoft
- Released: Jan 14, 2020
- Priority: Patch now (Closes CVE-2020-0646, exploited (CISA KEV))
- CVEs: 2, exploited: 1, on CISA KEV: 1
- Vendor advisory: https://support.microsoft.com/help/4535101

## Applies to

| Product | Release | Fixed in |
|---|---|---|
| [Microsoft .NET Framework 3.5 AND 4.7.2 on Windows 10 Version 1809 for 32-bit Systems](https://patchblox.com/security/data/product/microsoft/microsoft-.net-framework-3.5-and-4.7.2-on-windows-10-version-1809-for-32-bit-systems.md) |  |  |
| [Microsoft .NET Framework 3.5 AND 4.7.2 on Windows 10 Version 1809 for x64-based Systems](https://patchblox.com/security/data/product/microsoft/microsoft-.net-framework-3.5-and-4.7.2-on-windows-10-version-1809-for-x64-based-systems.md) |  |  |
| [Microsoft .NET Framework 3.5 AND 4.7.2 on Windows Server 2019](https://patchblox.com/security/data/product/microsoft/microsoft-.net-framework-3.5-and-4.7.2-on-windows-server-2019.md) |  |  |
| [Microsoft .NET Framework 3.5 AND 4.7.2 on Windows Server 2019 (Server Core installation)](https://patchblox.com/security/data/product/microsoft/microsoft-.net-framework-3.5-and-4.7.2-on-windows-server-2019-server-core-installation.md) |  |  |
| [Microsoft .NET Framework 3.5 AND 4.8 on Windows 10 Version 1809 for 32-bit Systems](https://patchblox.com/security/data/product/microsoft/microsoft-.net-framework-3.5-and-4.8-on-windows-10-version-1809-for-32-bit-systems.md) |  |  |
| [Microsoft .NET Framework 3.5 AND 4.8 on Windows 10 Version 1809 for x64-based Systems](https://patchblox.com/security/data/product/microsoft/microsoft-.net-framework-3.5-and-4.8-on-windows-10-version-1809-for-x64-based-systems.md) |  |  |
| [Microsoft .NET Framework 3.5 AND 4.8 on Windows Server 2019](https://patchblox.com/security/data/product/microsoft/microsoft-.net-framework-3.5-and-4.8-on-windows-server-2019.md) |  |  |
| [Microsoft .NET Framework 3.5 AND 4.8 on Windows Server 2019 (Server Core installation)](https://patchblox.com/security/data/product/microsoft/microsoft-.net-framework-3.5-and-4.8-on-windows-server-2019-server-core-installation.md) |  |  |

## CVEs this fix closes

| CVE | Priority | Component | CVSS | EPSS | Exploitation |
|---|---|---|---:|---:|---|
| [CVE-2020-0646](https://patchblox.com/security/data/cve/CVE-2020-0646.md) | Patch now | .NET Framework | n/a | 0.9922 | CISA KEV |
| [CVE-2020-0606](https://patchblox.com/security/data/cve/CVE-2020-0606.md) | Urgent | .NET Framework | n/a | 0.1834 |  |

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Data as of 2026-11-07T12:40:37Z 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

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