# KB4021903: June 2017 security update

KB4021903, released June 13, 2017, fixes 1 CVE across 3 products. One of them is being exploited (CVE-2017-8464); 1 on CISA KEV. Patch Radar priority: Patch now. The product is no longer supported.

- Web page: https://patchblox.com/security/fix/microsoft/kb4021903
- Platform: Microsoft
- Released: Jun 13, 2017
- Priority: Patch now (Closes CVE-2017-8464, exploited (CISA KEV))
- CVEs: 1, exploited: 1, on CISA KEV: 1
- Vendor advisory: https://support.microsoft.com/help/4021903

## Applies to

| Product | Release | Fixed in |
|---|---|---|
| [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 Itanium-Based Systems Service Pack 2](https://patchblox.com/security/data/product/microsoft/windows-server-2008-for-itanium-based-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) |  |  |

## CVEs this fix closes

| CVE | Priority | Component | CVSS | EPSS | Exploitation |
|---|---|---|---:|---:|---|
| [CVE-2017-8464](https://patchblox.com/security/data/cve/CVE-2017-8464.md) | Patch now | Windows Shell | 7.5 | 0.9003 | CISA KEV |

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 Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo