# CVE-2019-1254: Windows Hyper-V Information Disclosure Vulnerability

CVE-2019-1254 is fixed in 12 products on 1 platform, first by KB4516044, released September 10, 2019. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2019-1254
- Priority: Routine
- CVSS: 5.5 (Important)
- EPSS: 0.0133
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Vendor exploitability assessment: Exploitation Less Likely
- Published: Sep 10, 2019
- Vendor advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2019-1254

## Description

<p>An information disclosure vulnerability exists when Windows Hyper-V writes uninitialized memory to disk. An attacker could exploit the vulnerability by reading a file to recover kernel memory.</p> <p>To exploit the vulnerability, an attacker would first require access to a Hyper-V host.</p> <p>The security update addresses the vulnerability by ensuring Hyper-V properly initializes memory before writing it to disk.</p>

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Microsoft | Windows 10 Version 1607 for x64-based Systems | 14393.3204 | [KB4516044](https://patchblox.com/security/data/fix/microsoft/kb4516044.md) | Sep 10, 2019 |
| Microsoft | Windows 10 Version 1703 for x64-based Systems | 15063.2045 | [KB4516068](https://patchblox.com/security/data/fix/microsoft/kb4516068.md) | Sep 10, 2019 |
| Microsoft | Windows 10 Version 1709 for x64-based Systems | 16299.1387 | [KB4516066](https://patchblox.com/security/data/fix/microsoft/kb4516066.md) | Sep 10, 2019 |
| Microsoft | Windows 10 Version 1803 for x64-based Systems | 17134.1006 | [KB4516058](https://patchblox.com/security/data/fix/microsoft/kb4516058.md) | Sep 10, 2019 |
| Microsoft | Windows 10 Version 1809 for x64-based Systems | 17763.737 | [KB4512578](https://patchblox.com/security/data/fix/microsoft/kb4512578.md) | Sep 10, 2019 |
| Microsoft | Windows 10 Version 1903 for x64-based Systems | 18362.356 | [KB4515384](https://patchblox.com/security/data/fix/microsoft/kb4515384.md) | Sep 10, 2019 |
| Microsoft | Windows Server 2016 | 14393.3204 | [KB4516044](https://patchblox.com/security/data/fix/microsoft/kb4516044.md) | Sep 10, 2019 |
| Microsoft | Windows Server 2016 (Server Core installation) | 14393.3204 | [KB4516044](https://patchblox.com/security/data/fix/microsoft/kb4516044.md) | Sep 10, 2019 |
| Microsoft | Windows Server 2019 | 17763.737 | [KB4512578](https://patchblox.com/security/data/fix/microsoft/kb4512578.md) | Sep 10, 2019 |
| Microsoft | Windows Server 2019 (Server Core installation) | 17763.737 | [KB4512578](https://patchblox.com/security/data/fix/microsoft/kb4512578.md) | Sep 10, 2019 |
| Microsoft | Windows Server, version 1803  (Server Core Installation) | 17134.1006 | [KB4516058](https://patchblox.com/security/data/fix/microsoft/kb4516058.md) | Sep 10, 2019 |
| Microsoft | Windows Server, version 1903 (Server Core installation) | 18362.356 | [KB4515384](https://patchblox.com/security/data/fix/microsoft/kb4515384.md) | Sep 10, 2019 |

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Data as of 2026-11-08T00:53:09Z 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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