CVE-2025-4288
📋 TL;DR
A critical buffer overflow vulnerability in PCMan FTP Server 2.0.7 allows remote attackers to execute arbitrary code via the RNFR command handler. This affects all systems running the vulnerable FTP server version. Attackers can exploit this without authentication to potentially gain full control of affected systems.
💻 Affected Systems
- PCMan FTP Server
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution leading to complete system compromise, data theft, ransomware deployment, or creation of persistent backdoors.
Likely Case
Remote code execution resulting in system compromise, service disruption, and potential lateral movement within networks.
If Mitigated
Denial of service or service crashes if exploit attempts are blocked or fail, but system remains protected from code execution.
🎯 Exploit Status
Public exploit code is available, making this easily weaponizable by attackers.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: None available
Restart Required: Yes
Instructions:
1. Check if PCMan FTP Server 2.0.7 is installed. 2. Uninstall immediately. 3. Replace with alternative FTP server software. 4. No official patch exists from the vendor.
🔧 Temporary Workarounds
Block RNFR Command
allConfigure firewall or IPS to block RNFR commands to the FTP server
Network Segmentation
allIsolate FTP server from critical networks and internet access
🧯 If You Can't Patch
- Immediately disable or uninstall PCMan FTP Server 2.0.7
- Implement strict network segmentation and firewall rules to limit access to FTP service
🔍 How to Verify
Check if Vulnerable:
Check installed programs for 'PCMan FTP Server 2.0.7' or examine FTP server banner for version informationCheck Version:
Check Windows Programs and Features or examine FTP server banner on port 21Verify Fix Applied:
Verify PCMan FTP Server 2.0.7 is no longer installed or running📡 Detection & Monitoring
Log Indicators:
- Multiple RNFR command attempts
- Buffer overflow error messages in FTP logs
- Unusual FTP command sequences
Network Indicators:
- Exploit patterns in FTP traffic
- RNFR commands with excessive payload length
- Connection attempts followed by buffer overflow patterns
SIEM Query:
source="ftp.log" AND (command="RNFR" AND length>100) OR message="buffer overflow"