# CVE-2020-0621: Windows Security Feature Bypass Vulnerability

CVE-2020-0621 is fixed in 12 products on 1 platform, first by KB4534276, released January 14, 2020. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2020-0621
- Priority: Routine
- CVSS: 4.4 (Important)
- EPSS: 0.0104
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Vendor exploitability assessment: N/A
- Published: Jan 14, 2020
- Vendor advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2020-0621

## Description

<p>A security feature bypass vulnerability exists in Windows 10 when third party filters are called during a password update. Successful exploitation of the vulnerability could allow a user to make use of a blocked password for their account.</p> <p>To exploit the vulnerability, an attacker would need have access and the current password for the target user.</p> <p>The update addresses how password filters are called during a password update.</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 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 |

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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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