CVE-2025-6400
📋 TL;DR
This critical vulnerability in TOTOLINK N300RH routers allows remote attackers to execute arbitrary code via a buffer overflow in the HTTP POST message handler. Attackers can exploit this by sending specially crafted requests to the /boafrm/formPortFw endpoint, potentially taking full control of affected devices. Organizations using TOTOLINK N300RH routers with vulnerable firmware are at risk.
💻 Affected Systems
- TOTOLINK N300RH
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution leading to complete device compromise, lateral movement into internal networks, persistent backdoor installation, and data exfiltration.
Likely Case
Device takeover enabling traffic interception, credential theft, and use as pivot point for further attacks.
If Mitigated
Limited impact if devices are behind firewalls with strict inbound filtering and network segmentation.
🎯 Exploit Status
Proof-of-concept exploit code is publicly available, making exploitation straightforward for attackers.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: Not available
Restart Required: Yes
Instructions:
1. Check TOTOLINK website for firmware updates
2. Download latest firmware if available
3. Upload via router admin interface
4. Reboot router after update
🔧 Temporary Workarounds
Network Access Control
linuxBlock external access to router web interface
iptables -A INPUT -p tcp --dport 80 -j DROP
iptables -A INPUT -p tcp --dport 443 -j DROP
Disable Remote Management
allTurn off remote administration features
🧯 If You Can't Patch
- Isolate affected routers in separate VLAN with strict firewall rules
- Implement network monitoring for suspicious traffic to router management interfaces
🔍 How to Verify
Check if Vulnerable:
Check router firmware version in admin interface under System Status or Firmware Upgrade sectionCheck Version:
curl -s http://router-ip/boafrm/formSysCmd | grep -i versionVerify Fix Applied:
Verify firmware version has been updated to a version later than 6.1c.1390_B20191101📡 Detection & Monitoring
Log Indicators:
- Multiple POST requests to /boafrm/formPortFw with long service_type parameters
- Unusual process execution in router logs
Network Indicators:
- HTTP POST requests with abnormally long service_type parameter values
- Traffic patterns suggesting router compromise
SIEM Query:
source="router_logs" AND uri_path="/boafrm/formPortFw" AND http_method="POST" AND parameter_length>100