CVE-2024-45889
📋 TL;DR
DrayTek Vigor3900 routers version 1.5.1.3 contain a post-authentication command injection vulnerability in the mainfunction.cgi endpoint. Attackers with valid credentials can execute arbitrary commands on the device with root privileges. This affects organizations using these routers for network infrastructure.
💻 Affected Systems
- DrayTek Vigor3900
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Full device compromise allowing attackers to pivot to internal networks, intercept/modify traffic, install persistent backdoors, or use the device for further attacks.
Likely Case
Attackers with stolen or default credentials gain full control of the router, enabling traffic interception, network reconnaissance, and lateral movement.
If Mitigated
With strong authentication and network segmentation, impact is limited to the router itself without allowing network pivoting.
🎯 Exploit Status
Exploit requires authentication but is trivial to execute once credentials are obtained. Public proof-of-concept code exists.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: Unknown
Restart Required: No
Instructions:
Check DrayTek website for firmware updates. If available, download latest firmware and apply through web interface: System Maintenance > Firmware Upgrade.
🔧 Temporary Workarounds
Restrict Web Interface Access
allLimit access to the router's web management interface to trusted IP addresses only.
Change Default Credentials
allEnsure strong, unique passwords are set for all administrative accounts.
🧯 If You Can't Patch
- Isolate the router in a separate VLAN with strict firewall rules
- Disable remote management and only allow local console access
🔍 How to Verify
Check if Vulnerable:
Check if router is running version 1.5.1.3 via web interface: System Maintenance > Firmware InformationCheck Version:
Not applicable - check via web interfaceVerify Fix Applied:
Verify firmware version is updated beyond 1.5.1.3📡 Detection & Monitoring
Log Indicators:
- Unusual command execution in system logs
- Multiple failed login attempts followed by successful login
Network Indicators:
- Unusual outbound connections from router
- Traffic patterns suggesting command and control
SIEM Query:
source="vigor3900" AND (event="command execution" OR event="shell" OR event="system")