# CVE-2021-36955: Windows Common Log File System Driver Elevation of Privilege Vulnerability

> CVE-2021-36955: Windows Common Log File System Driver Elevation of Privilege Vulnerability. CVSS 7.8 (CVSS 3.1), in CISA KEV.

Canonical: https://rewindex.com/cve/CVE-2021-36955
Last updated: 2026-08-10T15:10:35Z

- Published: 2021-09-15 11:23 UTC · Updated: 2026-08-10 15:10 UTC · Assigner: microsoft
- CVSS: 7.8 (CVSS 3.1) · Severity: High · Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:F/RL:O/RC:C
- EPSS: 4.1%, 91th percentile (scored 2026-10-25)
- CISA KEV: yes, added 2021-11-03, federal due date 2021-11-17, ransomware use: Known

## Description

Windows Common Log File System Driver Elevation of Privilege Vulnerability

## CISA required action

Apply updates per vendor instructions.

## Affected vendors and products

- Microsoft: Windows 10 Version 1507
- Microsoft: Windows 10 Version 1607
- Microsoft: Windows 10 Version 1809
- Microsoft: Windows 10 Version 1909
- Microsoft: Windows 10 Version 2004
- Microsoft: Windows 10 Version 20H2
- Microsoft: Windows 10 Version 21H1
- Microsoft: Windows 7
- Microsoft: Windows 7 Service Pack 1
- Microsoft: Windows 8.1
- Microsoft: Windows Server 2008 R2 Service Pack 1
- Microsoft: Windows Server 2008 R2 Service Pack 1 (Server Core installation)
- Microsoft: Windows Server 2008 Service Pack 2
- Microsoft: Windows Server 2008 Service Pack 2 (Server Core installation)
- Microsoft: Windows Server 2012
- Microsoft: Windows Server 2012 R2
- Microsoft: Windows Server 2012 R2 (Server Core installation)
- Microsoft: Windows Server 2012 (Server Core installation)
- Microsoft: Windows Server 2016
- Microsoft: Windows Server 2016 (Server Core installation)
- Microsoft: Windows Server 2019
- Microsoft: Windows Server 2019 (Server Core installation)
- Microsoft: Windows Server 2022
- Microsoft: Windows Server version 2004
- Microsoft: Windows Server version 20H2

## References

- [CVE record on cve.org](https://www.cve.org/CVERecord?id=CVE-2021-36955)
- [NVD entry](https://nvd.nist.gov/vuln/detail/CVE-2021-36955)
- [https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-36955](https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-36955)

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_Sources: CVE records from the CVE Program (cve.org). CVE® is a registered trademark of The MITRE Corporation. (https://www.cve.org/) This product uses data from the NVD API but is not endorsed or certified by the NVD. (https://nvd.nist.gov/) Known Exploited Vulnerabilities catalog from CISA. (https://www.cisa.gov/known-exploited-vulnerabilities-catalog) EPSS scores from FIRST (Exploit Prediction Scoring System). (https://www.first.org/epss/)_


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Canonical: https://rewindex.com/cve/CVE-2021-36955 · Markdown: https://rewindex.com/cve/CVE-2021-36955.md · JSON: https://rewindex.com/api/v1/cves/CVE-2021-36955 · Data licensed CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) · Generated 2026-10-26T04:04:50.557Z