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
Published · last modified .
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.
EPSS exploit prediction
EPSS: 0.727 (99.4th percentile), scored .
High probability of exploitation in the next 30 days — patch promptly. 99th percentile — 99.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.729 · newest: 0.727 · change: -0.002
Affected products
Weakness classification (CWE)
Public proof-of-concept exploits
References
- www.monstaftp.com/notes/ (release-notes, Release Notes, patch)
- labs.watchtowr.com/whats-that-coming-over-the-hill-monsta-ftp-remote-code-execu… (Exploit, technical-description, Third Party Advisory, exploit)
- www.vulncheck.com/advisories/monsta-ftp-unauthenticated-arbitrary-file-upload (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.