---
id: CVE-2021-36955
title: Windows Common Log File System Driver Elevation of Privilege Vulnerability
summary: Windows Common Log File System Driver Elevation of Privilege Vulnerability
severity: high
cvss: 7.8
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H'
vendor: microsoft
product: windows_10_1507
affected:
  - windows_10_1507 < 10.0.10240.19060
  - windows_10_1607 < 10.0.14393.4651
  - windows_10_1809 < 10.0.17763.2183
  - windows_10_1909 < 10.0.18363.1801
  - windows_10_2004 < 10.0.19041.1237
  - windows_10_20h2 < 10.0.19042.1237
  - windows_10_21h1 < 10.0.19043.1237
  - windows_7
  - windows_8.1
  - windows_rt_8.1
  - windows_server_2004 < 10.0.19041.1237
  - windows_server_2008
  - windows_server_2008 = r2
  - windows_server_2012
  - windows_server_2016 < 10.0.14393.4651
  - windows_server_2019 < 10.0.17763.2183
  - windows_server_2022 < 10.0.20348.230
  - windows_server_20h2 < 10.0.19042.1237
patched:
  - windows_10_1507 10.0.10240.19060
  - windows_10_1607 10.0.14393.4651
  - windows_10_1809 10.0.17763.2183
  - windows_10_1909 10.0.18363.1801
  - windows_10_2004 10.0.19041.1237
  - windows_10_20h2 10.0.19042.1237
  - windows_10_21h1 10.0.19043.1237
  - windows_server_2004 10.0.19041.1237
  - windows_server_2016 10.0.14393.4651
  - windows_server_2019 10.0.17763.2183
  - windows_server_2022 10.0.20348.230
  - windows_server_20h2 10.0.19042.1237
published: '2021-09-15'
updated: '2026-08-10'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2021-36955'
references:
  - url: 'https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-36955'
    label: secure@microsoft.com
  - url: >-
      https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-36955
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: >-
      https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-36955
    label: 134c704f-9b21-4f2e-91b3-4a467353bcc0
tags:
  - nvd
  - kev
  - in-the-wild
  - exploit-available
epss: 0.04037
epssPercentile: 0.9024
kev: true
kevDateAdded: '2021-11-03'
kevDueDate: '2021-11-17'
kevRansomware: true
exploited: true
ingestedAt: '2026-08-11T16:47:01.213Z'
exploits:
  github: 1
  githubRepos:
    - 'https://github.com/JiaJinRong12138/CVE-2021-36955-EXP'
  checkedAt: '2026-09-26T09:05:26.829Z'
exploitAvailable: true
---

## Overview

Windows Common Log File System Driver Elevation of Privilege Vulnerability

## Affected

- `windows_10_1507 < 10.0.10240.19060`
- `windows_10_1607 < 10.0.14393.4651`
- `windows_10_1809 < 10.0.17763.2183`
- `windows_10_1909 < 10.0.18363.1801`
- `windows_10_2004 < 10.0.19041.1237`
- `windows_10_20h2 < 10.0.19042.1237`
- `windows_10_21h1 < 10.0.19043.1237`
- `windows_7`
- `windows_8.1`
- `windows_rt_8.1`
- `windows_server_2004 < 10.0.19041.1237`
- `windows_server_2008`
- `windows_server_2008 = r2`
- `windows_server_2012`
- `windows_server_2016 < 10.0.14393.4651`
- `windows_server_2019 < 10.0.17763.2183`
- `windows_server_2022 < 10.0.20348.230`
- `windows_server_20h2 < 10.0.19042.1237`

## Remediation

Upgrade past the affected range:

- `windows_10_1507 10.0.10240.19060`
- `windows_10_1607 10.0.14393.4651`
- `windows_10_1809 10.0.17763.2183`
- `windows_10_1909 10.0.18363.1801`
- `windows_10_2004 10.0.19041.1237`
- `windows_10_20h2 10.0.19042.1237`
- `windows_10_21h1 10.0.19043.1237`
- `windows_server_2004 10.0.19041.1237`
- `windows_server_2016 10.0.14393.4651`
- `windows_server_2019 10.0.17763.2183`
- `windows_server_2022 10.0.20348.230`
- `windows_server_20h2 10.0.19042.1237`