# KB4470638: December 2018 security update

KB4470638, released December 11, 2018, fixes 2 CVEs across 2 products. None of them is reported as exploited. Patch Radar priority: Urgent. The product is no longer supported.

- Web page: https://patchblox.com/security/fix/microsoft/kb4470638
- Platform: Microsoft
- Released: Dec 11, 2018
- Priority: Urgent (Closes CVE-2018-8540, rated Critical)
- CVEs: 2, exploited: 0, on CISA KEV: 0
- Vendor advisory: https://support.microsoft.com/help/4470638

## Applies to

| Product | Release | Fixed in |
|---|---|---|
| [Microsoft .NET Framework 4.6/4.6.1/4.6.2/4.7/4.7.1/4.7.2 on Windows Server 2012](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.md) |  |  |
| [Microsoft .NET Framework 4.6/4.6.1/4.6.2/4.7/4.7.1/4.7.2 on Windows Server 2012 (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-server-core-installation.md) |  |  |

## CVEs this fix closes

| CVE | Priority | Component | CVSS | EPSS | Exploitation |
|---|---|---|---:|---:|---|
| [CVE-2018-8540](https://patchblox.com/security/data/cve/CVE-2018-8540.md) | Urgent | .NET Framework | n/a | 0.2158 |  |
| [CVE-2018-8517](https://patchblox.com/security/data/cve/CVE-2018-8517.md) | High | .NET Framework | n/a | 0.0567 | Disclosed |

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