CVE-2025-5551
📋 TL;DR
CVE-2025-5551 is a critical buffer overflow vulnerability in FreeFloat FTP Server 1.0's SYSTEM command handler that allows remote attackers to execute arbitrary code. This affects all deployments of FreeFloat FTP Server 1.0. Attackers can exploit this without authentication to potentially gain complete control of affected systems.
💻 Affected Systems
- FreeFloat FTP Server
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution leading to full system compromise, data theft, ransomware deployment, or creation of persistent backdoors.
Likely Case
Remote code execution resulting in system compromise, data exfiltration, or use as pivot point in network attacks.
If Mitigated
Denial of service if exploit fails or system crashes before code execution.
🎯 Exploit Status
Public exploit code is available, making exploitation trivial for attackers with basic skills.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: N/A
Vendor Advisory: N/A
Restart Required: No
Instructions:
No official patch exists. FreeFloat FTP Server appears to be abandoned software. Migrate to a supported, secure FTP server solution.
🔧 Temporary Workarounds
Disable FreeFloat FTP Server
windowsImmediately stop and disable the FreeFloat FTP Server service
sc stop FreeFloatFTPServer
sc config FreeFloatFTPServer start= disabled
Network Segmentation
allBlock FTP ports (21/TCP, 20/TCP) at network perimeter and internal firewalls
🧯 If You Can't Patch
- Replace FreeFloat FTP Server with a supported alternative like FileZilla Server, vsftpd, or ProFTPD
- Implement strict network access controls to limit FTP server access to specific IP addresses only
🔍 How to Verify
Check if Vulnerable:
Check if FreeFloat FTP Server 1.0 is installed and running. Look for 'FreeFloat FTP Server' in installed programs or services.Check Version:
Check program files directory for FreeFloat FTP Server files or examine service propertiesVerify Fix Applied:
Verify FreeFloat FTP Server service is stopped and disabled, or confirm replacement with secure alternative is functioning.📡 Detection & Monitoring
Log Indicators:
- Unusual SYSTEM command usage in FTP logs
- Large buffer inputs to FTP commands
- Service crashes or restarts
Network Indicators:
- Exploit patterns in FTP traffic
- Unusual outbound connections from FTP server
SIEM Query:
source="ftp.log" AND (command="SYSTEM" AND size>1000) OR (event="buffer_overflow" OR event="crash")