# KB5003636: June 2021 security update

KB5003636, released June 8, 2021, fixes 3 CVEs across 9 products. One of them is being exploited (CVE-2021-33742); 1 on CISA KEV. Patch Radar priority: Patch now.

- Web page: https://patchblox.com/security/fix/microsoft/kb5003636
- Platform: Microsoft
- Released: Jun 8, 2021
- Priority: Patch now (Closes CVE-2021-33742, exploited (CISA KEV))
- CVEs: 3, exploited: 1, on CISA KEV: 1
- Vendor advisory: https://support.microsoft.com/help/5003636

## Applies to

| Product | Release | Fixed in |
|---|---|---|
| [Windows 7 for 32-bit Systems Service Pack 1](https://patchblox.com/security/data/product/microsoft/windows-7-for-32-bit-systems-service-pack-1.md) |  |  |
| [Windows 7 for x64-based Systems Service Pack 1](https://patchblox.com/security/data/product/microsoft/windows-7-for-x64-based-systems-service-pack-1.md) |  |  |
| [Windows 8.1 for 32-bit systems](https://patchblox.com/security/data/product/microsoft/windows-8.1-for-32-bit-systems.md) |  |  |
| [Windows 8.1 for x64-based systems](https://patchblox.com/security/data/product/microsoft/windows-8.1-for-x64-based-systems.md) |  |  |
| [Windows Server 2008 R2 for x64-based Systems Service Pack 1](https://patchblox.com/security/data/product/microsoft/windows-server-2008-r2-for-x64-based-systems-service-pack-1.md) |  |  |
| [Windows Server 2008 for 32-bit Systems Service Pack 2](https://patchblox.com/security/data/product/microsoft/windows-server-2008-for-32-bit-systems-service-pack-2.md) |  |  |
| [Windows Server 2008 for x64-based Systems Service Pack 2](https://patchblox.com/security/data/product/microsoft/windows-server-2008-for-x64-based-systems-service-pack-2.md) |  |  |
| [Windows Server 2012](https://patchblox.com/security/data/product/microsoft/windows-server-2012.md) |  |  |
| [Windows Server 2012 R2](https://patchblox.com/security/data/product/microsoft/windows-server-2012-r2.md) |  |  |

## CVEs this fix closes

| CVE | Priority | Component | CVSS | EPSS | Exploitation |
|---|---|---|---:|---:|---|
| [CVE-2021-33742](https://patchblox.com/security/data/cve/CVE-2021-33742.md) | Patch now | Windows MSHTML Platform | 7.5 | 0.5941 | CISA KEV |
| [CVE-2021-31959](https://patchblox.com/security/data/cve/CVE-2021-31959.md) | Urgent | Microsoft Scripting Engine | 6.4 | 0.0923 | More likely |
| [CVE-2021-31971](https://patchblox.com/security/data/cve/CVE-2021-31971.md) | Routine | Windows HTML Platform | 6.8 | 0.0209 |  |

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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