CVE-2025-3375
📋 TL;DR
CVE-2025-3375 is a critical buffer overflow vulnerability in PCMan FTP Server 2.0.7's CDUP command handler that allows remote attackers to execute arbitrary code or crash the service. This affects all systems running the vulnerable FTP server version. Attackers can exploit this without authentication over the network.
💻 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, or ransomware deployment.
Likely Case
Service crash causing denial of service, potentially followed by remote code execution if exploit is refined.
If Mitigated
Service disruption with limited impact if proper network segmentation and monitoring are in place.
🎯 Exploit Status
Public exploit code available at provided reference URL. Attack requires sending crafted CDUP command to FTP port.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: None available
Restart Required: Yes
Instructions:
1. Check for updated version from vendor. 2. If no patch, migrate to alternative FTP server software. 3. Disable or remove PCMan FTP Server 2.0.7.
🔧 Temporary Workarounds
Network Access Control
allBlock FTP port (21/tcp) at firewall or restrict access to trusted IPs only
# Windows Firewall: netsh advfirewall firewall add rule name="Block FTP" dir=in action=block protocol=TCP localport=21
# Linux iptables: iptables -A INPUT -p tcp --dport 21 -j DROP
Service Disablement
windowsStop and disable the FTP service
# Windows: sc stop "PCMan FTP Server" && sc config "PCMan FTP Server" start= disabled
# Linux service equivalent if applicable
🧯 If You Can't Patch
- Replace PCMan FTP Server with alternative secure FTP solution like FileZilla Server or vsftpd
- Implement strict network segmentation to isolate FTP server from critical systems
🔍 How to Verify
Check if Vulnerable:
Check if PCMan FTP Server version 2.0.7 is installed and running on port 21Check Version:
# Check Windows services: sc query "PCMan FTP Server" || Check installed programs in Control PanelVerify Fix Applied:
Verify service is stopped/removed or replaced with different FTP server📡 Detection & Monitoring
Log Indicators:
- Multiple failed CDUP commands
- Unusual long CDUP command parameters
- Service crash logs
Network Indicators:
- Unusually long FTP CDUP commands (> typical length)
- Traffic to FTP port from unexpected sources
SIEM Query:
source="ftp.log" AND (command="CDUP" AND length>100) OR (event="service_crash" AND service="PCMan FTP")