Monsta FTP - RCE (CVE-2025-34299)

CVE-2025-34299 is a critical vulnerability in Monsta FTP versions 2.11 and earlier that allows unauthenticated attackers to upload arbitrary files, potentially leading to remote code execution. Exploiting this flaw, threat actors can compromise the server by uploading malicious files from a rogue (S)FTP server, making it a significant risk for web-based file management environments.

CrowdSec has been tracking this vulnerability and its exploits since 12th of November 2025.

CrowdSec network data shows that most actors exploiting CVE-2025-34299 rely on broad, untargeted scans with minimal filtering. The activity is largely automated and opportunistic in nature. Telemetry from the CrowdSec network also shows that exploitation activity for CVE-2025-34299 remains steady week-over-week. Attack volumes are consistent with long-term trends, indicating sustained interest from threat actors. CVE-2025-34299 continues to be an active part of the threat landscape and will likely remain this way for the forseeable future.

Attackers exploit Monsta FTP by sending crafted POST requests to /mftp/application/api/api.php with malicious SFTP connection parameters, enabling remote file writes and potential code execution on the server.