CVE-2024-41586
📋 TL;DR
A stack-based buffer overflow vulnerability in DrayTek Vigor310 devices allows remote attackers to execute arbitrary code by sending a specially crafted long query string to the cgi-bin/ipfedr.cgi component. This affects all Vigor310 devices running firmware version 4.3.2.6 and earlier. Attackers can potentially gain full control of affected devices.
💻 Affected Systems
- DrayTek Vigor310
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution leading to complete device compromise, lateral movement into internal networks, and persistent backdoor installation.
Likely Case
Device takeover enabling network traffic interception, credential theft, and use as a foothold for further attacks.
If Mitigated
Limited impact if devices are behind firewalls with strict inbound filtering and network segmentation.
🎯 Exploit Status
Exploitation requires sending a specially crafted HTTP request to the vulnerable endpoint. Public research includes proof-of-concept details.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 4.3.2.7 or later
Vendor Advisory: https://www.draytek.com/support/security-advisory/
Restart Required: Yes
Instructions:
1. Log into Vigor310 web interface. 2. Navigate to System Maintenance > Firmware Upgrade. 3. Download latest firmware from DrayTek support site. 4. Upload and apply firmware update. 5. Reboot device after update completes.
🔧 Temporary Workarounds
Block External Access
linuxRestrict access to the web management interface from untrusted networks.
iptables -A INPUT -p tcp --dport 80 -s ! TRUSTED_NETWORK -j DROP
iptables -A INPUT -p tcp --dport 443 -s ! TRUSTED_NETWORK -j DROP
Disable Unnecessary Services
allDisable remote management if not required.
🧯 If You Can't Patch
- Place device behind a WAF or reverse proxy with buffer overflow protection rules.
- Implement strict network segmentation to isolate vulnerable devices from critical assets.
🔍 How to Verify
Check if Vulnerable:
Check firmware version via web interface: System Maintenance > Firmware Information. If version is 4.3.2.6 or earlier, device is vulnerable.Check Version:
curl -k https://DEVICE_IP/cgi-bin/ipfedr.cgi?version (Note: This may trigger the vulnerability - use with caution in isolated environment)Verify Fix Applied:
Confirm firmware version is 4.3.2.7 or later after applying update.📡 Detection & Monitoring
Log Indicators:
- Unusually long query strings in web server logs
- Multiple failed requests to cgi-bin/ipfedr.cgi
- Buffer overflow error messages in system logs
Network Indicators:
- HTTP requests with abnormally long query parameters to /cgi-bin/ipfedr.cgi
- Traffic patterns suggesting exploit attempts
SIEM Query:
source="vigor310_logs" AND (uri="/cgi-bin/ipfedr.cgi" AND query_length>1000)