CVE-2021-43226
Windows Common Log File System Driver Elevation of Privilege Vulnerability
ACTIVELY EXPLOITED IN THE WILD
This vulnerability is listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.
Microsoft Windows Privilege Escalation Vulnerability
Microsoft Windows
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
10/6/2025
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-43226 ; https://nvd.nist.gov/vuln/detail/CVE-2021-43226
Vulnerability Summary
CVSS v3 Score
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CVSS v2 Score
AV:L/AC:L/Au:N/C:P/I:P/A:P
EPSS Score (Exploitation Probability)
This vulnerability has a 8.39% probability of being exploited in the next 30 days, ranking higher than 92% of all scored CVEs.
CWE Classification
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Similar SeverityHIGH
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