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

Overview

Severity

High (CVSS 7.8)

CVSS Vector

CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:F/RL:O/RC:C

Category

Elevation of Privilege

Exploit Status

Not Exploited

Exploitation Likelihood

More Likely

Patch Tuesday

2021-Sep

Released

2021-09-14

Last Updated

2021-09-23

EPSS Score

20.64% (percentile: 95.6%)

CISA KEV

Listed — due 2021-11-17

Known Exploits (1)

• Microsoft Windows Common Log File System (CLFS) Driver Privilege Escalation Vulnerability — added 2022-07-18T07:08:56Z

Detection & Weaponization (1 sources)

Maturity: Exploit

• GitHub PoC: 1 repositories

Affected Products (42)

Windows

• Windows 10 Version 1809 for 32-bit Systems
• Windows 10 Version 1809 for x64-based Systems
• Windows 10 Version 1809 for ARM64-based Systems
• Windows Server 2019
• Windows Server 2019 (Server Core installation)
• Windows 10 Version 1909 for 32-bit Systems
• Windows 10 Version 1909 for x64-based Systems
• Windows 10 Version 1909 for ARM64-based Systems
• Windows 10 Version 21H1 for x64-based Systems
• Windows 10 Version 21H1 for ARM64-based Systems
• Windows 10 Version 21H1 for 32-bit Systems
• Windows Server 2022
• Windows Server 2022 (Server Core installation)
• Windows 10 Version 2004 for 32-bit Systems
• Windows 10 Version 2004 for ARM64-based Systems
• Windows 10 Version 2004 for x64-based Systems
• Windows Server, version 2004 (Server Core installation)
• Windows 10 Version 20H2 for x64-based Systems
• Windows 10 Version 20H2 for 32-bit Systems
• Windows 10 Version 20H2 for ARM64-based Systems
• Windows Server, version 20H2 (Server Core Installation)
• Windows 10 for 32-bit Systems
• Windows 10 for x64-based Systems
• Windows 10 Version 1607 for 32-bit Systems
• Windows 10 Version 1607 for x64-based Systems
• Windows Server 2016
• Windows Server 2016 (Server Core installation)
• Windows 8.1 for 32-bit systems
• Windows 8.1 for x64-based systems
• Windows RT 8.1
• Windows Server 2012
• Windows Server 2012 (Server Core installation)
• Windows Server 2012 R2
• Windows Server 2012 R2 (Server Core installation)

ESU

• Windows 7 for 32-bit Systems Service Pack 1
• Windows 7 for x64-based Systems Service Pack 1
• Windows Server 2008 for 32-bit Systems Service Pack 2
• Windows Server 2008 for 32-bit Systems Service Pack 2 (Server Core installation)
• Windows Server 2008 for x64-based Systems Service Pack 2
• Windows Server 2008 for x64-based Systems Service Pack 2 (Server Core installation)
• Windows Server 2008 R2 for x64-based Systems Service Pack 1
• Windows Server 2008 R2 for x64-based Systems Service Pack 1 (Server Core installation)

Security Updates (14)

• 5005568
• 5005566
• 5005565
• 5005575
• 5005569
• 5005573
• 5005633
• 5005615
• 5005613
• 5005627
• 5005606
• 5005618
• 5005623
• 5005607

Revision History

• 2021-09-14: Information published.
• 2021-09-23: For all CVEs affecting Windows that were released on September 14, 2021: 1) In the Security Updates table, the Build Numbers for KB KB5005565 have been corrected for all affected editions of the following versions of Windows 10: Windows 10, version 2004, all editions; Windows Server, version 2004 (Server Core installation); Windows 10, version 20H2; Windows Server, version 20H2 (Server Core Installation); Windows 10, version 21H1. 2) For CVEs where Windows Server 2022 is affected the links have been updated to point to information related to 5005575. Customers whose Windows devices are configured to receive automatic updates do not need to take any further action.