# CVE-2021-36934: Windows Elevation of Privilege Vulnerability

CVE-2021-36934 is fixed in 15 products on 1 platform, first by KB5005030, released August 10, 2021. It is being exploited: CISA added it to the Known Exploited Vulnerabilities catalog on February 10, 2022. Patch Radar priority: Patch now.

- Web page: https://patchblox.com/security/cve/CVE-2021-36934
- Priority: Patch now
- CVSS: 7.8 (Important)
- EPSS: 0.6725
- CISA KEV: listed Feb 10, 2022, federal due date Feb 24, 2022
- Exploited (vendor report): no
- Publicly disclosed: yes
- Vendor exploitability assessment: Exploitation More Likely
- Published: Jul 20, 2021
- Vendor advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-36934

## Description

<p>An elevation of privilege vulnerability exists because of overly permissive Access Control Lists (ACLs) on multiple system files, including the Security Accounts Manager (SAM) database. An attacker who successfully exploited this vulnerability could run arbitrary code with SYSTEM privileges. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights.</p> <p>An attacker must have the ability to execute code on a victim system to exploit this vulnerability.</p> <p>After installing this security update, you <em>must</em> manually delete all shadow copies of system files, including the SAM database, to fully mitigate this vulnerabilty. <strong>Simply installing this security update will not fully mitigate this vulnerability.</strong> See <a href="https://support.microsoft.com/topic/1ceaa637-aaa3-4b58-a48b-baf72a2fa9e7">KB5005357- Delete Volume Shadow Copies</a>.</p>

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Microsoft | Windows 10 Version 1809 for 32-bit Systems | 17763.2114 | [KB5005030](https://patchblox.com/security/data/fix/microsoft/kb5005030.md) | Aug 10, 2021 |
| Microsoft | Windows 10 Version 1809 for ARM64-based Systems | 17763.2114 | [KB5005030](https://patchblox.com/security/data/fix/microsoft/kb5005030.md) | Aug 10, 2021 |
| Microsoft | Windows 10 Version 1809 for x64-based Systems | 17763.2114 | [KB5005030](https://patchblox.com/security/data/fix/microsoft/kb5005030.md) | Aug 10, 2021 |
| Microsoft | Windows 10 Version 1909 for 32-bit Systems | 18363.1734 | [KB5005031](https://patchblox.com/security/data/fix/microsoft/kb5005031.md) | Aug 10, 2021 |
| Microsoft | Windows 10 Version 1909 for ARM64-based Systems | 18363.1734 | [KB5005031](https://patchblox.com/security/data/fix/microsoft/kb5005031.md) | Aug 10, 2021 |
| Microsoft | Windows 10 Version 1909 for x64-based Systems | 18363.1734 | [KB5005031](https://patchblox.com/security/data/fix/microsoft/kb5005031.md) | Aug 10, 2021 |
| Microsoft | Windows 10 Version 2004 for 32-bit Systems |  | [KB5005033](https://patchblox.com/security/data/fix/microsoft/kb5005033.md) | Aug 10, 2021 |
| Microsoft | Windows 10 Version 2004 for ARM64-based Systems |  | [KB5005033](https://patchblox.com/security/data/fix/microsoft/kb5005033.md) | Aug 10, 2021 |
| Microsoft | Windows 10 Version 2004 for x64-based Systems |  | [KB5005033](https://patchblox.com/security/data/fix/microsoft/kb5005033.md) | Aug 10, 2021 |
| Microsoft | Windows 10 Version 20H2 for 32-bit Systems |  | [KB5005033](https://patchblox.com/security/data/fix/microsoft/kb5005033.md) | Aug 10, 2021 |
| Microsoft | Windows 10 Version 20H2 for ARM64-based Systems |  | [KB5005033](https://patchblox.com/security/data/fix/microsoft/kb5005033.md) | Aug 10, 2021 |
| Microsoft | Windows 10 Version 20H2 for x64-based Systems |  | [KB5005033](https://patchblox.com/security/data/fix/microsoft/kb5005033.md) | Aug 10, 2021 |
| Microsoft | Windows 10 Version 21H1 for 32-bit Systems |  | [KB5005033](https://patchblox.com/security/data/fix/microsoft/kb5005033.md) | Aug 10, 2021 |
| Microsoft | Windows 10 Version 21H1 for ARM64-based Systems |  | [KB5005033](https://patchblox.com/security/data/fix/microsoft/kb5005033.md) | Aug 10, 2021 |
| Microsoft | Windows 10 Version 21H1 for x64-based Systems |  | [KB5005033](https://patchblox.com/security/data/fix/microsoft/kb5005033.md) | Aug 10, 2021 |

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Data as of 2026-11-08T19:12:23Z 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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