CVE-2024-4040 — CrushFTP VFS Sandbox Escape Vulnerability

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

CISA SSVC assessment CISA

Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

• Documented patch — www.crushftp.com (NIST National Vulnerability Database)
• Documented patch — www.crushftp.com (NIST National Vulnerability Database)
• Documented patch — www.reddit.com (NIST National Vulnerability Database)

CISA required action CISA

Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.

US federal deadline: May 1, 2024 — passed 897 day(s) ago

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

1. Identify exposed assets running the affected vendor/product/version combinations (CrushFTP CrushFTP).
2. Treat as emergency remediation: the CVE is in CISA KEV (confirmed exploitation).
3. The attack is network-based and needs no privileges: restrict exposure (ACLs, VPN, WAF) until patched.
4. Apply the fixed version or the patch documented under Remediation.
5. EPSS ahead of 100% of scored CVEs: prioritize it in the patch queue.
6. Search available logs for exploit probes matching the vulnerability class (injection), errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Every base score collected

Sources score independently and may disagree; each row says who scored it and under which version.

Weakness MITRE

Weakness class according to MITRE’s CWE catalog.

CWE-94 · Code Injection

Other CVEs with this weakness →

CISA KEV details CISA

CISA lists a CVE once it has evidence of exploitation against real targets.

CISA records ransomware use only for campaigns it has confirmed, so “Unknown” means unrecorded, not ruled out. The deadline binds US federal agencies; for everyone else it is a reference date.

Public exploits, PoCs and detection templates

Public code that demonstrates or tests the flaw raises the odds of mass exploitation — and Nuclei templates help find vulnerable assets in your environment.

Warning: public PoCs are sometimes disguised malware. Use them only for authorized testing in an isolated environment. This portal does not host exploit code — it only points to the sources.

EPSS over time FIRST

Oct 12, 2026 → Oct 14, 2026 · 3 reading(s) · max 99.54%

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

• Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).
• Look for parameters with command/query metacharacters and unexpected child processes of the service.
• Hunt retroactively in logs from before Apr 24, 2024 (KEV listing): exploitation may have started earlier.

Timeline

What happened to this CVE, newest first.

• 2026
• Affected products added · crushftp/crushftp
  Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
• SSVC assessment updated
  Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
• Record published
  Oct 13, 2026
• Fix documented
  Oct 13, 2026 · NIST National Vulnerability Database
• Affected products added · crushftp/crushftp
  Oct 13, 2026 · NIST National Vulnerability Database
• CVSS changed · 10.0
  Oct 13, 2026 · NIST National Vulnerability Database
• Source status changed · → Analyzed
  Oct 13, 2026 · NIST National Vulnerability Database
• Added to CISA KEV (detected)
  Oct 13, 2026 · CISA Known Exploited Vulnerabilities
• Record created in this database
  Oct 13, 2026 · CISA Known Exploited Vulnerabilities
• 2024
• Added to CISA KEV catalog
  Apr 23, 2024 · CISA
• CVE published
  Apr 22, 2024 · directcyber

Source activity

Repeated readings are counted rather than listed.

• 2× References added · Oct 13, 2026 – Oct 13, 2026
• 1× Official description updated · Oct 13, 2026 – Oct 13, 2026

References

14 on the record

• www.crushftp.com/crush10wiki/Wiki.jsp
  Patch, Vendor Advisory, vendor-advisory, NIST National Vulnerability Database
• www.crushftp.com/crush11wiki/Wiki.jsp
  Patch, Vendor Advisory, vendor-advisory, NIST National Vulnerability Database
• www.reddit.com/r/cybersecurity/comments/1c850i2/all_versions_of_crush_ftp_are_vulner
  Issue Tracking, Patch, related, NIST National Vulnerability Database
• www.cisa.gov/known-exploited-vulnerabilities-catalog
  US Government Resource, NIST National Vulnerability Database
• github.com/airbus-cert/CVE-2024-4040
  Exploit, Third Party Advisory, exploit, NIST National Vulnerability Database
• www.bleepingcomputer.com/news/security/crushftp-warns-users-to-patch-exploited-zero-day-immedi
  GitHub Security Advisories
• nvd.nist.gov/vuln/detail/CVE-2024-4040
  GitHub Security Advisories
• www.reddit.com/r/cybersecurity/comments/1c850i2/all_versions_of_crush_ftp_are_vulner
  GitHub Security Advisories
• www.reddit.com/r/crowdstrike/comments/1c88788/situational_awareness_20240419_crushft
  GitHub Security Advisories
• github.com/advisories/GHSA-46vf-c8gj-2pgq
  GitHub Security Advisories
• www.rapid7.com/blog/post/2024/04/23/etr-unauthenticated-crushftp-zero-day-enables-co
  Third Party Advisory, third-party-advisory, NIST National Vulnerability Database
• www.rapid7.com/blog/post/2024/04/23/etr-unauthenticated-crushftp-zero-day-enables-co
  GitHub Security Advisories
• www.bleepingcomputer.com/news/security/crushftp-warns-users-to-patch-exploited-zero-day-immedi
  Press/Media Coverage, Third Party Advisory, media-coverage, NIST National Vulnerability Database
• www.reddit.com/r/crowdstrike/comments/1c88788/situational_awareness_20240419_crushft
  Exploit, Issue Tracking, third-party-advisory, NIST National Vulnerability Database

Elsewhere on this site

Related CVEs (same products)

• Medium CVE-2025-63419 Cross-site Scripting (XSS) in CrushFTP Nov 12, 2025
• Medium CVE-2025-63420 Cross-site Scripting (XSS) in CrushFTP Nov 7, 2025
• Critical CVE-2025-54309 CrushFTP Unprotected Alternate Channel Vulnerability KEV Jul 18, 2025
• Critical CVE-2025-31161 CrushFTP Authentication Bypass Vulnerability KEV Apr 3, 2025
• Medium CVE-2023-48795 Prefix Truncation Attack against ChaCha20-Poly1305 and Encrypt-then-MAC aka Terrapin Dec 18, 2023

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

• No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
• No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
• No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2024-4040 is "CrushFTP VFS Sandbox Escape Vulnerability", rated Critical. It affects CrushFTP (CrushFTP); versions are in the scope table. It is in CISA KEV: there is evidence of real-world exploitation. CVSS 10.0 describes technical severity. EPSS 99.54% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

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