CVE-2024-39762
📋 TL;DR
This CVE describes multiple OS command injection vulnerabilities in the Wavlink AC3000 router's internet.cgi functionality. An authenticated attacker can send specially crafted HTTP requests to execute arbitrary commands on the device. This affects Wavlink AC3000 routers running vulnerable firmware versions.
💻 Affected Systems
- Wavlink AC3000 M33A8
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete device compromise allowing attacker to install persistent backdoors, pivot to internal networks, intercept all network traffic, and use device for botnet activities.
Likely Case
Attacker gains full control of router to modify network settings, intercept credentials, deploy malware to connected devices, or use router for DDoS attacks.
If Mitigated
Limited impact if proper network segmentation, authentication controls, and monitoring are in place to detect and block exploitation attempts.
🎯 Exploit Status
Exploitation requires authenticated access but is straightforward once credentials are obtained. The Talos report provides technical details that could be weaponized.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: Not available
Restart Required: Yes
Instructions:
1. Check Wavlink website for firmware updates. 2. Download latest firmware for AC3000. 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
Network Segmentation
allIsolate router management interface from untrusted networks
Access Control
linuxRestrict access to router admin interface using firewall rules
iptables -A INPUT -p tcp --dport 80 -s TRUSTED_IP -j ACCEPT
iptables -A INPUT -p tcp --dport 443 -s TRUSTED_IP -j ACCEPT
iptables -A INPUT -p tcp --dport 80 -j DROP
iptables -A INPUT -p tcp --dport 443 -j DROP
🧯 If You Can't Patch
- Change default credentials and use strong authentication
- Disable remote administration and restrict admin interface to local network only
🔍 How to Verify
Check if Vulnerable:
Check firmware version in router admin interface under System Status or Firmware Update sectionCheck Version:
Login to router web interface and navigate to firmware/status pageVerify Fix Applied:
Verify firmware version has been updated to a version later than V5030.210505📡 Detection & Monitoring
Log Indicators:
- Unusual HTTP POST requests to internet.cgi
- Multiple failed authentication attempts followed by successful login
- Commands containing shell metacharacters in HTTP parameters
Network Indicators:
- HTTP requests with shell commands in netmask parameter
- Unusual outbound connections from router to external IPs
- Port scans originating from router
SIEM Query:
source="router_logs" AND (uri="*internet.cgi*" AND method="POST" AND (param="*netmask*" AND value="*;*" OR value="*|*" OR value="*`*"))