CVE-2021-46227
📋 TL;DR
This CVE describes a command injection vulnerability in D-Link DI-7200GV2.E1 routers that allows attackers to execute arbitrary commands via specific parameters in the proxy_client.asp function. Attackers can gain full control of affected devices, potentially compromising network security. Only D-Link DI-7200GV2.E1 routers running firmware version 21.04.09E1 are affected.
💻 Affected Systems
- D-Link DI-7200GV2.E1
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete device takeover leading to network compromise, data exfiltration, lateral movement to other systems, and persistent backdoor installation.
Likely Case
Router compromise allowing traffic interception, credential theft, and use as pivot point for further attacks.
If Mitigated
Limited impact if device is behind firewall with restricted WAN access and proper network segmentation.
🎯 Exploit Status
Public proof-of-concept code exists, and command injection vulnerabilities are frequently weaponized. No authentication is required for exploitation.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Check vendor advisory for latest patched version
Vendor Advisory: https://supportannouncement.us.dlink.com/announcement/publication.aspx?name=SAP10284
Restart Required: Yes
Instructions:
1. Access D-Link support site 2. Download latest firmware for DI-7200GV2.E1 3. Backup current configuration 4. Upload firmware via web interface 5. Reboot device 6. Restore configuration if needed
🔧 Temporary Workarounds
Disable WAN access to management interface
allBlock external access to router web interface
Configure firewall to block port 80/443 from WAN to router management IP
Network segmentation
allIsolate router management interface to separate VLAN
Create separate management VLAN and restrict access to authorized IPs only
🧯 If You Can't Patch
- Immediately block all WAN access to the router's management interface
- Implement strict network segmentation and monitor for suspicious outbound connections
🔍 How to Verify
Check if Vulnerable:
Check firmware version in router web interface under System > FirmwareCheck Version:
Login to router web interface and navigate to System > Firmware InformationVerify Fix Applied:
Verify firmware version is updated beyond v21.04.09E1 and test proxy_client.asp functionality📡 Detection & Monitoring
Log Indicators:
- Unusual command execution in system logs
- Multiple failed login attempts to web interface
- Suspicious outbound connections from router
Network Indicators:
- Unexpected traffic patterns from router
- Connections to known malicious IPs
- Port scanning originating from router
SIEM Query:
source="router_logs" AND ("proxy_client.asp" OR "command injection" OR "unauthorized access")🔗 References
- https://github.com/pjqwudi/my_vuln/blob/main/D-link/vuln_10/10.md
- https://supportannouncement.us.dlink.com/announcement/publication.aspx?name=SAP10284
- https://www.dlink.com/en/security-bulletin/
- https://github.com/pjqwudi/my_vuln/blob/main/D-link/vuln_10/10.md
- https://supportannouncement.us.dlink.com/announcement/publication.aspx?name=SAP10284
- https://www.dlink.com/en/security-bulletin/
