What is CVE-2025-34299?

CVE-2025-34299 is a critical-severity vulnerability in Monstaftp Monsta_ftp, classified under Unrestricted Upload of File with Dangerous Type. CVSS score: 9.8/10. Published 2025-11-07.

How severe is CVE-2025-34299?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Is CVE-2025-34299 known to be exploited?

4 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

Arbitrary file upload in Monstaftp Monsta_ftp

CVE-2025-34299

Monsta FTP versions 2.11 and earlier contain a vulnerability that allows unauthenticated arbitrary file uploads. This flaw enables attackers to execute arbitrary code by uploading a specially crafted file from a malicious (S)FTP server.

Vulnerability class: Unrestricted File Upload

EPSS: 0.727 (99.4th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

Monstaftp Monsta_ftp
Monsta Limited Of New Zealand Ftp — versions 0

Weakness classification (CWE)

CWE-434 — Unrestricted Upload of File with Dangerous Type

Public proof-of-concept exploits

References

disclosure@vulncheck.com (release-notes, Release Notes, patch)
disclosure@vulncheck.com (Exploit, technical-description, Third Party Advisory, exploit)
disclosure@vulncheck.com (Third Party Advisory, third-party-advisory)

Frequently asked questions

What is CVE-2025-34299?: CVE-2025-34299 is a critical-severity vulnerability in Monstaftp Monsta_ftp, classified under Unrestricted Upload of File with Dangerous Type. CVSS score: 9.8/10. Published 2025-11-07.
How severe is CVE-2025-34299?: Critical severity. CVSS v3 base score is 9.8 out of 10.
Is CVE-2025-34299 known to be exploited?: 4 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.