# CVE-2020-0638: Update Notification Manager Elevation of Privilege Vulnerability

CVE-2020-0638 is fixed in 20 products on 1 platform, first by KB4534276, released January 14, 2020. It is being exploited: CISA added it to the Known Exploited Vulnerabilities catalog on May 23, 2022, with known ransomware use. Patch Radar priority: Patch now.

- Web page: https://patchblox.com/security/cve/CVE-2020-0638
- Priority: Patch now
- CVSS: 7.8 (Important)
- EPSS: 0.0254
- CISA KEV: listed May 23, 2022, federal due date Jun 13, 2022, known ransomware use
- Exploited (vendor report): no
- Publicly disclosed: no
- Vendor exploitability assessment: Exploitation Less Likely
- Published: Jan 14, 2020
- Vendor advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2020-0638

## Description

<p>An elevation of privilege vulnerability exists in the way the Update Notification Manager handles files.</p> <p>To exploit this vulnerability, an attacker would first have to gain execution on the victim system. An attacker could then run a specially crafted application to elevate privileges.</p> <p>The security update addresses the vulnerability by correcting how the Update Notification Manager handles files.</p>

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Microsoft | Windows 10 Version 1709 for 32-bit Systems | 16299.1625 | [KB4534276](https://patchblox.com/security/data/fix/microsoft/kb4534276.md) | Jan 14, 2020 |
| Microsoft | Windows 10 Version 1709 for ARM64-based Systems | 16299.1625 | [KB4534276](https://patchblox.com/security/data/fix/microsoft/kb4534276.md) | Jan 14, 2020 |
| Microsoft | Windows 10 Version 1709 for x64-based Systems | 16299.1625 | [KB4534276](https://patchblox.com/security/data/fix/microsoft/kb4534276.md) | Jan 14, 2020 |
| Microsoft | Windows 10 Version 1803 for 32-bit Systems | 17134.1246 | [KB4534293](https://patchblox.com/security/data/fix/microsoft/kb4534293.md) | Jan 14, 2020 |
| Microsoft | Windows 10 Version 1803 for ARM64-based Systems | 17134.1246 | [KB4534293](https://patchblox.com/security/data/fix/microsoft/kb4534293.md) | Jan 14, 2020 |
| Microsoft | Windows 10 Version 1803 for x64-based Systems | 17134.1246 | [KB4534293](https://patchblox.com/security/data/fix/microsoft/kb4534293.md) | Jan 14, 2020 |
| Microsoft | Windows 10 Version 1809 for 32-bit Systems | 17763.973 | [KB4534273](https://patchblox.com/security/data/fix/microsoft/kb4534273.md) | Jan 14, 2020 |
| Microsoft | Windows 10 Version 1809 for ARM64-based Systems | 17763.973 | [KB4534273](https://patchblox.com/security/data/fix/microsoft/kb4534273.md) | Jan 14, 2020 |
| Microsoft | Windows 10 Version 1809 for x64-based Systems | 17763.973 | [KB4534273](https://patchblox.com/security/data/fix/microsoft/kb4534273.md) | Jan 14, 2020 |
| Microsoft | Windows 10 Version 1903 for 32-bit Systems |  | [KB4528760](https://patchblox.com/security/data/fix/microsoft/kb4528760.md) | Jan 14, 2020 |
| Microsoft | Windows 10 Version 1903 for ARM64-based Systems |  | [KB4528760](https://patchblox.com/security/data/fix/microsoft/kb4528760.md) | Jan 14, 2020 |
| Microsoft | Windows 10 Version 1903 for x64-based Systems |  | [KB4528760](https://patchblox.com/security/data/fix/microsoft/kb4528760.md) | Jan 14, 2020 |
| Microsoft | Windows 10 Version 1909 for 32-bit Systems |  | [KB4528760](https://patchblox.com/security/data/fix/microsoft/kb4528760.md) | Jan 14, 2020 |
| Microsoft | Windows 10 Version 1909 for ARM64-based Systems |  | [KB4528760](https://patchblox.com/security/data/fix/microsoft/kb4528760.md) | Jan 14, 2020 |
| Microsoft | Windows 10 Version 1909 for x64-based Systems |  | [KB4528760](https://patchblox.com/security/data/fix/microsoft/kb4528760.md) | Jan 14, 2020 |
| Microsoft | Windows Server 2019 | 17763.973 | [KB4534273](https://patchblox.com/security/data/fix/microsoft/kb4534273.md) | Jan 14, 2020 |
| Microsoft | Windows Server 2019 (Server Core installation) | 17763.973 | [KB4534273](https://patchblox.com/security/data/fix/microsoft/kb4534273.md) | Jan 14, 2020 |
| Microsoft | Windows Server, version 1803  (Server Core Installation) | 17134.1246 | [KB4534293](https://patchblox.com/security/data/fix/microsoft/kb4534293.md) | Jan 14, 2020 |
| Microsoft | Windows Server, version 1903 (Server Core installation) |  | [KB4528760](https://patchblox.com/security/data/fix/microsoft/kb4528760.md) | Jan 14, 2020 |
| Microsoft | Windows Server, version 1909 (Server Core installation) |  | [KB4528760](https://patchblox.com/security/data/fix/microsoft/kb4528760.md) | Jan 14, 2020 |

---

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

Free to use with attribution: show "Data: Patchblox Patch Radar" with a link to https://patchblox.com/security/patch-radar. Terms, including what needs a written agreement: https://patchblox.com/security/patch-radar/use-the-data

Product names, logos and trademarks shown on Patch Radar belong to their respective owners. They are used only to identify the software each security fix applies to and to help readers find their platform. Their use does not imply any affiliation with, or endorsement by, those owners, and Patchblox is not affiliated with any of them.