# KB5066840: October 2025 security update

KB5066840, released October 14, 2025, fixes 3 CVEs across 10 products. None of them is reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/fix/microsoft/kb5066840
- Platform: Microsoft
- Released: Oct 14, 2025
- Priority: High (Closes CVE-2025-59295, high severity)
- CVEs: 3, exploited: 0, on CISA KEV: 0
- Vendor advisory: https://support.microsoft.com/help/5066840

## Applies to

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

## CVEs this fix closes

| CVE | Priority | Component | CVSS | EPSS | Exploitation |
|---|---|---|---:|---:|---|
| [CVE-2025-59295](https://patchblox.com/security/data/cve/CVE-2025-59295.md) | High | Internet Explorer | 8.8 | 0.0190 |  |
| [CVE-2025-59208](https://patchblox.com/security/data/cve/CVE-2025-59208.md) | High | Windows MapUrlToZone | 7.1 | 0.0050 |  |
| [CVE-2025-58739](https://patchblox.com/security/data/cve/CVE-2025-58739.md) | Routine | Windows File Explorer | 6.5 | 0.0082 |  |

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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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