CVE-2017-16885
📋 TL;DR
This vulnerability allows remote attackers to access sensitive information from FiberHome LM53Q1 routers without authentication. Attackers can retrieve device version, firmware ID, connected users' MAC addresses, and potentially change passwords. Anyone using the affected router model with the vulnerable firmware is at risk.
💻 Affected Systems
- FiberHome LM53Q1
📦 What is this software?
Lm53q1 Firmware by Fiberhome
⚠️ Risk & Real-World Impact
Worst Case
Complete device compromise allowing attackers to change passwords, monitor all connected users, and potentially pivot to internal network attacks.
Likely Case
Information disclosure of connected devices and network configuration, enabling targeted attacks against users.
If Mitigated
Limited impact if device is behind firewall with restricted WAN access and proper network segmentation.
🎯 Exploit Status
Simple HTTP requests to specific endpoints bypass authentication. Exploit code is publicly available.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: Not available
Restart Required: No
Instructions:
No official patch available. Check with FiberHome for firmware updates or consider device replacement.
🔧 Temporary Workarounds
Disable WAN access to web portal
linuxConfigure firewall to block external access to router web interface (typically port 80/443)
iptables -A INPUT -p tcp --dport 80 -j DROP
iptables -A INPUT -p tcp --dport 443 -j DROP
Network segmentation
allIsolate router management interface to separate VLAN with restricted access
🧯 If You Can't Patch
- Replace affected devices with patched or different vendor equipment
- Implement strict network monitoring for unauthorized access attempts to router management interface
🔍 How to Verify
Check if Vulnerable:
Attempt to access http://[router-ip]/api/v1/system/info without authentication. If it returns device information, it's vulnerable.Check Version:
Check router web interface or use curl: curl -s http://[router-ip]/api/v1/system/info | grep versionVerify Fix Applied:
Verify that unauthenticated requests to /api/v1/ endpoints return authentication errors or are blocked.📡 Detection & Monitoring
Log Indicators:
- Unauthenticated access to /api/v1/ endpoints
- Multiple failed authentication attempts followed by successful API calls
Network Indicators:
- HTTP GET requests to router IP on port 80/443 with /api/v1/ paths from external IPs
SIEM Query:
source="router_logs" AND (url_path="/api/v1/system/info" OR url_path="/api/v1/user/list") AND auth_status="none"