CVE-2021-43226: Microsoft Windows Privilege Escalation Vulnerability

Published Dec 14, 2021
·
Updated

Microsoft Windows Common Log File System Driver contains a privilege escalation vulnerability that could allow a local, privileged attacker to bypass certain security mechanisms.

Other sources

Windows Common Log File System Driver Elevation of Privilege Vulnerability

NVD

Affected Software

86 affected componentsFixes available
Microsoft Windows 10
Microsoft Windows 10=20h2
Microsoft Windows 10=21h1
Microsoft Windows 10=1607
Microsoft Windows 10=1809
Microsoft Windows 10=1909
Microsoft Windows 10=2004
Microsoft Windows 11
Microsoft Windows 7=sp1
Microsoft Windows 8.1
Microsoft Windows RT 8.1
Microsoft Windows Server=20h2
Microsoft Windows Server=2022
Microsoft Windows Server 2008=sp2
Microsoft Windows Server 2008=r2-sp1
Microsoft Windows Server 2012
Microsoft Windows Server 2012=r2
Microsoft Windows Server 2016
Microsoft Windows Server 2016=2004
Microsoft Windows Server 2019
Microsoft Windows
Microsoft Windows 10 1507<10.0.10240.19145
Microsoft Windows 10 1507<10.0.10240.19145
Microsoft Windows 10 1607<10.0.14393.4825
Microsoft Windows 10 1607<10.0.14393.4825
Microsoft Windows 10 1809<10.0.17763.2366
Microsoft Windows 10 1909<10.0.18363.1977
Microsoft Windows 10 2004<10.0.19041.1415
Microsoft Windows 10 20h2<10.0.19042.1415
Microsoft Windows 10 20h2<10.0.19042.1415
Microsoft Windows 10 21h1<10.0.19043.1415
Microsoft Windows 10 21h2<10.0.19044.1415
Microsoft Windows 11 21h2<10.0.22000.376
Microsoft Windows Server 2004<10.0.19041.1415
Microsoft Windows Server 2008=sp2
Microsoft Windows Server 2008=sp2
Microsoft Windows Server 2016<10.0.14393.4825
Microsoft Windows Server 2019<10.0.17763.2366
Microsoft Windows Server 2022<10.0.20348.405
Microsoft Windows Server 20h2<10.0.19042.1415
Microsoft Windows Server 2012<6.2.9200.23545, <6.2.9200.23540
6.2.9200.235456.2.9200.23540
Microsoft Windows Server 2012 R2<6.3.9600.20207
6.3.9600.20207
Microsoft Windows Server 2008 R2<6.1.7601.25796
6.1.7601.25796
Microsoft Windows Server 2012 R2<6.3.9600.20207
6.3.9600.20207
Microsoft Windows Server 2008<6.0.6003.21309
6.0.6003.21309
Microsoft Windows Server 2008<6.0.6003.21309
6.0.6003.21309
Microsoft Windows Server 2008 R2<6.1.7601.25796
6.1.7601.25796
Microsoft Windows Server 2012<6.2.9200.23545, <6.2.9200.23540
6.2.9200.235456.2.9200.23540
Microsoft Windows Server 2008<6.0.6003.21309
6.0.6003.21309
Microsoft Windows Server 2008<6.0.6003.21309
6.0.6003.21309
Microsoft Windows RT 8.1<6.3.9600.20207
6.3.9600.20207
Microsoft Windows 8.1 for x64-based systems<6.3.9600.20207
6.3.9600.20207
Microsoft Windows Server 2016<10.0.14393.4825
10.0.14393.4825
Microsoft Windows 7<6.1.7601.25796
6.1.7601.25796
Microsoft Windows 7<6.1.7601.25796
6.1.7601.25796
Microsoft Windows 8.1 for 32-bit systems<6.3.9600.20207
6.3.9600.20207
Microsoft Windows Server 2016<10.0.14393.4825
10.0.14393.4825
Microsoft Windows 10<10.0.10240.19145
10.0.10240.19145
Microsoft Windows 10=1607
10.0.14393.4825
Microsoft Windows 10=21H2
10.0.19044.1415
Microsoft Windows 10=1607
10.0.14393.4825
Microsoft Windows 10=21H2
10.0.19044.1415
Microsoft Windows 10<10.0.10240.19145
10.0.10240.19145
Microsoft Windows 11=21H2
10.0.22000.376
Microsoft Windows 10=21H2
10.0.19044.1415
Microsoft Windows 10=2004
10.0.19041.1415
Microsoft Windows 11=21H2
10.0.22000.376
Microsoft Windows 10=20H2
10.0.19042.1415
Microsoft Windows 10=2004
10.0.19041.1415
Microsoft Windows 10=20H2
10.0.19042.1415
Microsoft Windows Server=20H2
10.0.19042.1415
Microsoft Windows Server 2022<10.0.20348.405
10.0.20348.405
Microsoft Windows Server 2022<10.0.20348.405
10.0.20348.405
Microsoft Windows 10=2004
10.0.19041.1415
Microsoft Windows Server=2004
10.0.19041.1415
Microsoft Windows 10=21H1
10.0.19043.1415
Microsoft Windows 10=1909
10.0.18363.1977
Microsoft Windows 10=1909
10.0.18363.1977
Microsoft Windows 10=21H1
10.0.19043.1415
Microsoft Windows 10=21H1
10.0.19043.1415
Microsoft Windows 10=1909
10.0.18363.1977
Microsoft Windows Server 2019<10.0.17763.2366
10.0.17763.2366
Microsoft Windows 10=1809
10.0.17763.2366
Microsoft Windows Server 2019<10.0.17763.2366
10.0.17763.2366
Microsoft Windows 10=1809
10.0.17763.2366
Microsoft Windows 10=1809
10.0.17763.2366

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 6.2.9200.23545Fixed in 6.2.9200.23540Patch KB5008255
  2. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 6.3.9600.20207Patch KB5008285
  3. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 6.1.7601.25796Patch KB5008282
  4. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 6.0.6003.21309Patch KB5008271
  5. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 6.3.9600.20207Patch KB5008263
  6. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 10.0.14393.4825Patch KB5008207
  7. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 10.0.10240.19145Patch KB5008230
  8. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 10.0.19044.1415Patch KB5008212
  9. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 10.0.22000.376Patch KB5008215
  10. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 10.0.19041.1415Patch KB5008212
  11. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 10.0.19042.1415Patch KB5008212
  12. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 10.0.20348.405Patch KB5008223
  13. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 10.0.19043.1415Patch KB5008212
  14. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 10.0.18363.1977Patch KB5008206
  15. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 10.0.17763.2366Patch KB5008218

Event History

Dec 14, 2021
CVE Published
via Microsoft·08:00 AM
Data Sourced
via Microsoft·08:00 AM
DescriptionSeverityWeakness
Data Sourced
via Microsoft·08:00 AM
Affected Software
Updated
via Microsoft·08:00 AM
Description
Dec 15, 2021
CVE Published
via MITRE·02:15 PM
Data Sourced
via MITRE·02:15 PM
DescriptionSeverity
Data Sourced
via NVD·03:15 PM
RemedyDescriptionSeverityAffected Software
Oct 6, 2025
Known Exploited
via CISA·12:00 AM
Data Sourced
via CISA·12:00 AM
RemedyDescriptionAffected Software
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Frequently Asked Questions

1

What is the severity of CVE-2021-43226?

CVE-2021-43226 has a severity rating of important, indicating a significant risk.

2

How do I fix CVE-2021-43226?

To mitigate CVE-2021-43226, users should apply the latest security updates provided by Microsoft.

3

Which systems are affected by CVE-2021-43226?

CVE-2021-43226 affects multiple versions of Microsoft Windows, including Windows 10, Windows 7, Windows 8.1, and various Windows Server editions.

4

What type of vulnerability is CVE-2021-43226?

CVE-2021-43226 is classified as an elevation of privilege vulnerability in the Windows Common Log File System Driver.

5

Can CVE-2021-43226 be exploited remotely?

CVE-2021-43226 requires local access to the system for exploitation, but it can allow an attacker to gain higher privileges if successfully executed.

Contact

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