CVE-2022-24521: in the CISA KEV catalogue
Microsoft Windows CLFS Driver Privilege Escalation Vulnerability. CISA added CVE-2022-24521 to the Known Exploited Vulnerabilities catalogue on 2022-04-13 with a default due date of 2022-05-04. Known ransomware campaign use: Known. Forensic triage flag: No.
Microsoft Windows Common Log File System (CLFS) Driver contains an unspecified vulnerability that allows for privilege escalation. (CISA description)
- Vendor / product
- Microsoft Windows
- CWE
- CWE-787, CWE-1285
- CISA required action
- Apply updates per vendor instructions.
- EPSS
- 7.1%, percentile 94 (scored 2026-11-03)
EPSS puts about 7.1 in 100 odds (7.1%) on exploitation activity being observed in the next 30 days. Its score is higher than or equal to that of 94% of scored CVEs. This is a model estimate about exploitation anywhere, not about your environment.
Vendor and reference links (from CISA)
Your own deadline under CISA BOD 26-04 depends on exposure, automatability and technical impact: work it out with the BOD 26-04 calculator.
Frequently asked questions
Is CVE-2022-24521 in the CISA KEV catalogue?
Yes. CISA added CVE-2022-24521 (Microsoft Windows CLFS Driver Privilege Escalation Vulnerability) to the Known Exploited Vulnerabilities catalogue on 2022-04-13. CISA's default due date for it is 2022-05-04.
Is CVE-2022-24521 used in ransomware attacks?
CISA marks known ransomware campaign use as Known for CVE-2022-24521.
What should I do about CVE-2022-24521?
CISA's required action: Apply updates per vendor instructions.
Sources
- CISA, Known Exploited Vulnerabilities Catalog (accessed 2026-11-03)
- FIRST, Exploit Prediction Scoring System (EPSS) (EPSS by FIRST; scores generated by Empirical Security)
- NVD record for CVE-2022-24521