CVE-2023-50215
📋 TL;DR
This vulnerability allows network-adjacent attackers to execute arbitrary commands as root on D-Link G416 routers without authentication. Attackers can exploit improper input validation in the HTTP service to achieve remote code execution. All users of affected D-Link G416 routers are at risk.
💻 Affected Systems
- D-Link G416 router
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete compromise of router with root access, allowing attackers to intercept/modify all network traffic, install persistent malware, pivot to internal network devices, and brick the device.
Likely Case
Router takeover leading to DNS hijacking, credential theft from network traffic, and installation of backdoors for persistent access.
If Mitigated
No impact if router is patched or isolated from untrusted networks.
🎯 Exploit Status
Exploit details published by ZDI. Simple HTTP request with command injection payload can trigger RCE.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Check D-Link support for latest firmware
Vendor Advisory: https://supportannouncement.us.dlink.com/announcement/publication.aspx?name=SAP10367
Restart Required: Yes
Instructions:
1. Visit D-Link support site 2. Download latest firmware for G416 3. Log into router admin interface 4. Navigate to firmware update section 5. Upload and apply new firmware 6. Reboot router
🔧 Temporary Workarounds
Disable HTTP service
allDisable the vulnerable HTTP service on port 80 if not needed
Router-specific: Check admin interface for service disable options
Network segmentation
linuxIsolate router from untrusted networks using firewall rules
iptables -A INPUT -p tcp --dport 80 -j DROP (on upstream firewall)
🧯 If You Can't Patch
- Replace router with patched model or different vendor
- Implement strict network segmentation to limit access to router management interface
🔍 How to Verify
Check if Vulnerable:
Check router firmware version against D-Link advisory. Test with non-destructive payload like 'id' command via HTTP request to port 80.Check Version:
Check router web interface or use nmap scan: nmap -sV -p 80 [router_ip]Verify Fix Applied:
Verify firmware version is updated to patched version. Attempt exploitation with test payload should fail.📡 Detection & Monitoring
Log Indicators:
- Unusual HTTP requests to port 80 with shell metacharacters
- Unexpected process execution from HTTP service
Network Indicators:
- HTTP requests containing command injection patterns (;, |, $, etc.) to router port 80
SIEM Query:
source="router_logs" AND dest_port=80 AND (http_uri="*;*" OR http_uri="*|*" OR http_uri="*$(*" OR http_uri="*`*`)