# KB5026366: May 2023 security update

KB5026366, released May 9, 2023, fixes 1 CVE across 10 products. None of them is reported as exploited. Patch Radar priority: Urgent.

- Web page: https://patchblox.com/security/fix/microsoft/kb5026366
- Platform: Microsoft
- Released: May 9, 2023
- Priority: Urgent (Closes CVE-2023-29324, exploitation more likely)
- CVEs: 1, exploited: 0, on CISA KEV: 0
- Vendor advisory: https://support.microsoft.com/help/5026366

## 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-2023-29324](https://patchblox.com/security/data/cve/CVE-2023-29324.md) | Urgent | Windows MSHTML Platform | 6.5 | 0.0284 | More likely |

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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