# KB5004959: July 2021 security update

KB5004959, released July 2, 2021, fixes 1 CVE across 4 products. One of them is being exploited (CVE-2021-34527); 1 on CISA KEV. Patch Radar priority: Patch now. The product is no longer supported.

- Web page: https://patchblox.com/security/fix/microsoft/kb5004959
- Platform: Microsoft
- Released: Jul 2, 2021
- Priority: Patch now (Closes CVE-2021-34527, exploited (CISA KEV, ransomware))
- CVEs: 1, exploited: 1, on CISA KEV: 1
- Vendor advisory: https://support.microsoft.com/help/5004959

## 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 32-bit Systems Service Pack 2 (Server Core installation)](https://patchblox.com/security/data/product/microsoft/windows-server-2008-for-32-bit-systems-service-pack-2-server-core-installation.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 2008 for x64-based Systems Service Pack 2 (Server Core installation)](https://patchblox.com/security/data/product/microsoft/windows-server-2008-for-x64-based-systems-service-pack-2-server-core-installation.md) |  |  |

## CVEs this fix closes

| CVE | Priority | Component | CVSS | EPSS | Exploitation |
|---|---|---|---:|---:|---|
| [CVE-2021-34527](https://patchblox.com/security/data/cve/CVE-2021-34527.md) | Patch now | Windows Print Spooler Components | 8.8 | 0.9979 | CISA KEV, Ransomware, Disclosed |

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 Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo