CVE-2025-5217
📋 TL;DR
A critical buffer overflow vulnerability in FreeFloat FTP Server 1.0.0 allows remote attackers to execute arbitrary code or crash the service by sending specially crafted RMDIR commands. This affects all systems running FreeFloat FTP Server 1.0.0 with the vulnerable component enabled. The vulnerability is remotely exploitable without authentication.
💻 Affected Systems
- FreeFloat FTP Server
📦 What is this software?
Ftp Server by Freefloat
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution leading to complete system compromise, data theft, or ransomware deployment.
Likely Case
Service disruption through denial of service (crash) or limited code execution depending on exploit sophistication.
If Mitigated
If network segmentation and strict firewall rules are in place, impact is limited to the FTP service itself.
🎯 Exploit Status
Public exploit code is available, making exploitation straightforward for attackers.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: N/A
Vendor Advisory: N/A
Restart Required: No
Instructions:
No official patch is available. Consider migrating to a supported FTP server solution.
🔧 Temporary Workarounds
Disable RMDIR command via configuration
windowsModify FreeFloat FTP Server configuration to disable the RMDIR command handler if possible.
Check FreeFloat FTP Server configuration file for RMDIR command settings
Network segmentation and firewall rules
windowsRestrict access to the FTP server to only trusted IP addresses or internal networks.
Example Windows Firewall: netsh advfirewall firewall add rule name="Block FTP External" dir=in action=block protocol=TCP localport=21 remoteip=any
🧯 If You Can't Patch
- Immediately isolate the FreeFloat FTP Server from internet access using firewall rules.
- Migrate to a modern, supported FTP server application with active security updates.
🔍 How to Verify
Check if Vulnerable:
Check if FreeFloat FTP Server version 1.0.0 is installed and running on the system.Check Version:
Check FreeFloat FTP Server interface or documentation for version information.Verify Fix Applied:
Verify the server has been upgraded to a different FTP solution or that RMDIR command is disabled.📡 Detection & Monitoring
Log Indicators:
- Multiple failed RMDIR commands with unusual parameters
- FTP server crash logs
- Unusual process execution following FTP connections
Network Indicators:
- Excessive RMDIR commands to FTP port 21
- Traffic patterns matching known exploit payloads
SIEM Query:
source="ftp.log" AND command="RMDIR" AND (parameter_length>100 OR parameter contains non-ASCII)