# CVE-2020-17087: Microsoft Windows Kernel Privilege Escalation Vulnerability

Source: https://junglewise.ai/threats/cve-2020-17087-microsoft-windows-kernel-privilege-escalation-vulnerability  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2021-11-03. Updated: 2026-05-10  
License: CC BY 4.0 with a link back

CVE-2020-17087 · Severity: critical · CVSS 7.8 · Exploited in the wild · Published 2021-11-03

The Microsoft Windows kernel contains a local elevation of privilege vulnerability due to incorrect calculation of buffer sizes (CWE-131). An attacker who successfully exploits this vulnerability could gain elevated system privileges.

Technologies: [Microsoft Windows](https://junglewise.ai/threats/technologies/windows). Vendors: [Microsoft](https://junglewise.ai/threats/vendors/microsoft).

## Quick answers

**Is CVE-2020-17087 exploited in the wild?** Yes. CVE-2020-17087 is known to be exploited in the wild, first recorded on 3 November 2021. Treat it as urgent.

**How severe is CVE-2020-17087?** Critical severity, with a CVSS score of 7.8, published 3 November 2021.

**Which products and versions are affected?** Microsoft Windows 7 Service Pack 1; Microsoft Windows 8.1; Microsoft Windows RT 8.1; Microsoft Windows 10 1507, 1607, 1803, 1809, 1903, 1909, 2004, 20H2; and 4 more.

**Is there a fix for CVE-2020-17087?** A patch was published on 2024-11-21: Microsoft advisory updated/referenced Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2020-17087 attacked?** It is attacked with local access, in an operating system.

**Am I affected by CVE-2020-17087?** Check whether you run Microsoft Windows. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Affected products

- Microsoft Windows 7 Service Pack 1
- Microsoft Windows 8.1
- Microsoft Windows RT 8.1
- Microsoft Windows 10 1507, 1607, 1803, 1809, 1903, 1909, 2004, 20H2
- Microsoft Windows Server 2008 Service Pack 2, R2 Service Pack 2
- Microsoft Windows Server 2012 R2
- Microsoft Windows Server 2016 1903, 1909, 2004, 20H2
- Microsoft Windows Server 2019

## Timeline

- 2020-11-16: disclosed: Initial analysis by NIST
- 2021-11-03: kev added: Added to CISA Known Exploited Vulnerabilities Catalog
- 2024-11-21: patched: Microsoft advisory updated/referenced
- 2021-11-03: advisory: Publication date of the vulnerability record

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