CVE-2021-43226

Vulnerability details

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

Added to CISA KEV: 2025-10-06

Ransomware campaign use: Known

CISA due date: 2025-10-27

Defensive guidance from CISA

Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

This is the source's required-action field, not an independently validated patch procedure. Refer to the vendor for exact affected versions and fixes.