CVE-2024-4040: in the CISA KEV catalogue
CrushFTP VFS Sandbox Escape Vulnerability. CISA added CVE-2024-4040 to the Known Exploited Vulnerabilities catalogue on 2024-04-24 with a default due date of 2024-05-01. Known ransomware campaign use: Unknown. Forensic triage flag: No.
CrushFTP contains an unspecified sandbox escape vulnerability that allows a remote attacker to escape the CrushFTP virtual file system (VFS). (CISA description)
- Vendor / product
- CrushFTP CrushFTP
- CWE
- CWE-1336
- CISA required action
- Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
- EPSS
- 100%, percentile 99 (scored 2026-11-03)
EPSS puts nearly every time in 100 odds (100%) on exploitation activity being observed in the next 30 days. Its score is higher than or equal to that of 99% 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-2024-4040 in the CISA KEV catalogue?
Yes. CISA added CVE-2024-4040 (CrushFTP VFS Sandbox Escape Vulnerability) to the Known Exploited Vulnerabilities catalogue on 2024-04-24. CISA's default due date for it is 2024-05-01.
Is CVE-2024-4040 used in ransomware attacks?
CISA marks known ransomware campaign use as Unknown for CVE-2024-4040. That means CISA lacks confirmation, not that ransomware groups do not use it.
What should I do about CVE-2024-4040?
CISA's required action: Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
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-2024-4040