CVE-2021-43226

Description

Windows Common Log File System Driver Elevation of Privilege Vulnerability

Scoring

• CVSS: 7.8 (HIGH, 3.1)
• EPSS exploitation probability: Not yet available
• EPSS percentile: Not yet available

CISA KEV status

• Added to KEV: 2025-10-06
• Remediation due date: 2025-10-27
• Known ransomware campaign use: Known

References

• https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-43226
• https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-43226
• https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-43226

More from Microsoft

• CVE-2026-96951 — Windows
• CVE-2026-65660 — SharePoint
• CVE-2026-81963 — Windows
• CVE-2026-85880 — Windows
• CVE-2019-1068 — SQL Server