CVE-2024-8211
📋 TL;DR
This critical vulnerability allows remote attackers to execute arbitrary commands on affected D-Link NAS devices by injecting malicious input into the f_newly_dev parameter of the hd_config.cgi script. It affects multiple D-Link NAS models that are no longer supported by the vendor. Attackers can exploit this without authentication to gain full control of vulnerable devices.
💻 Affected Systems
- D-Link DNS-120
- DNR-202L
- DNS-315L
- DNS-320
- DNS-320L
- DNS-320LW
- DNS-321
- DNR-322L
- DNS-323
- DNS-325
- DNS-326
- DNS-327L
- DNR-326
- DNS-340L
- DNS-343
- DNS-345
- DNS-726-4
- DNS-1100-4
- DNS-1200-05
- DNS-1550-04
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete device compromise leading to data theft, ransomware deployment, lateral movement to internal networks, and persistent backdoor installation.
Likely Case
Remote code execution allowing attackers to steal data, install malware, or use device as part of botnet for DDoS attacks.
If Mitigated
Limited impact if devices are isolated from internet and internal networks with strict network segmentation.
🎯 Exploit Status
Public exploit code available on GitHub. Simple HTTP request with command injection payload required.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: N/A
Vendor Advisory: https://supportannouncement.us.dlink.com/security/publication.aspx?name=SAP10383
Restart Required: No
Instructions:
No official patch available. Vendor recommends retiring and replacing all affected devices.
🔧 Temporary Workarounds
Network Isolation
linuxBlock all external access to affected devices and restrict internal access to specific IPs only.
iptables -A INPUT -p tcp --dport 80 -s 192.168.1.0/24 -j ACCEPT
iptables -A INPUT -p tcp --dport 80 -j DROP
CGI Script Disable
linuxRemove or rename the vulnerable CGI script to prevent exploitation.
mv /cgi-bin/hd_config.cgi /cgi-bin/hd_config.cgi.disabled
🧯 If You Can't Patch
- Immediately disconnect affected devices from internet and place behind strict firewall rules
- Replace all affected devices with supported alternatives as soon as possible
🔍 How to Verify
Check if Vulnerable:
Check if device model is in affected list and has web interface accessible. Test with harmless command injection payload: curl 'http://device-ip/cgi-bin/hd_config.cgi?f_newly_dev=test;echo vulnerable'Check Version:
Check web interface admin page or device label for model numberVerify Fix Applied:
Verify device is no longer accessible from untrusted networks and vulnerable script is disabled or removed.📡 Detection & Monitoring
Log Indicators:
- HTTP requests to /cgi-bin/hd_config.cgi with shell metacharacters in parameters
- Unusual process execution from web server user
- Failed authentication attempts followed by CGI access
Network Indicators:
- HTTP POST/GET requests to hd_config.cgi with semicolons, pipes, or backticks in parameters
- Outbound connections from NAS device to suspicious IPs
SIEM Query:
source="web_logs" AND uri="/cgi-bin/hd_config.cgi" AND (param="f_newly_dev" AND value MATCHES "[;|`&]"