Actively exploited in the wild

Microsoft Windows Common Log File System (CLFS) Driver Privilege Escalation Vulnerability

Microsoft - Windows · Listed in the CISA KEV since 2021-11-03. This indicates confirmed attacks in production environments.

Required action: Apply updates per vendor instructions.

CVE-2021-36955

HighCVSS 7.8KEV

Published: 15/09/2021(UTC)Updated: 10/08/2026(UTC)Translated: 10/08/2026(UTC)NVD NIST

Exploitation Probability (EPSS)

High risk

3.23%

87th percentile - higher than 87% of all known CVEs

Elevation of privilege vulnerability in Windows Common Log File System Driver. Could be exploited to gain elevated privileges.

Risk of privilege escalation and system takeover.

Apply Windows security updates.

Original NVD description (English source)

Windows Common Log File System Driver Elevation of Privilege Vulnerability