CVE-2025-25609
📋 TL;DR
This buffer overflow vulnerability in TOTOlink A3002R routers allows attackers to execute arbitrary code by sending specially crafted requests to the formIpv6Setup interface. The vulnerability affects all users running the vulnerable firmware version on these routers. Successful exploitation could lead to complete device compromise.
💻 Affected Systems
- TOTOlink A3002R
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution leading to full router compromise, credential theft, network pivoting, and persistent backdoor installation.
Likely Case
Router crash/reboot causing service disruption, or limited code execution allowing network reconnaissance and traffic interception.
If Mitigated
Denial of service from crash if exploit fails, or no impact if input validation blocks malicious payloads.
🎯 Exploit Status
Exploitation requires sending crafted HTTP requests to the vulnerable endpoint. No authentication bypass is mentioned, suggesting authentication may be required.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Check vendor for updated firmware version
Vendor Advisory: Unknown - check TOTOlink official website
Restart Required: Yes
Instructions:
1. Check TOTOlink website for firmware updates. 2. Download latest firmware for A3002R. 3. Log into router admin interface. 4. Navigate to firmware update section. 5. Upload and apply new firmware. 6. Reboot router after update completes.
🔧 Temporary Workarounds
Disable IPv6 Configuration Interface
allPrevent access to the vulnerable formIpv6Setup interface
Restrict Web Interface Access
allLimit access to router admin interface to trusted IPs only
🧯 If You Can't Patch
- Isolate router on separate VLAN with strict firewall rules
- Disable remote administration and limit web interface to local network only
🔍 How to Verify
Check if Vulnerable:
Check router firmware version in admin interface. If version is V1.1.1-B20200824.0128, device is vulnerable.Check Version:
Log into router web interface and check System Status or Firmware Information pageVerify Fix Applied:
Verify firmware version has been updated to a version later than V1.1.1-B20200824.0128.📡 Detection & Monitoring
Log Indicators:
- Unusual HTTP POST requests to /bin/boa with formIpv6Setup parameter
- Router crash/reboot logs
- Multiple failed authentication attempts followed by IPv6 configuration requests
Network Indicators:
- HTTP traffic to router on port 80/443 with unusually long static_ipv6 parameter values
- Sudden router reboot events
SIEM Query:
source="router_logs" AND (uri="/bin/boa" AND param="static_ipv6" AND length(value)>100) OR event="router_reboot"