CVE-2024-8131
📋 TL;DR
This critical vulnerability allows remote attackers to execute arbitrary commands on affected D-Link NAS devices by exploiting a command injection flaw in the web interface's module management function. Attackers can compromise the device, potentially gaining full control. This affects multiple D-Link NAS models that are no longer supported by the vendor.
💻 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 allowing attackers to execute arbitrary commands with root privileges, install malware, pivot to internal networks, and exfiltrate or destroy data.
Likely Case
Remote code execution leading to device takeover, ransomware deployment, or creation of a persistent backdoor for further attacks.
If Mitigated
Limited impact if devices are isolated behind firewalls with strict network segmentation and access controls.
🎯 Exploit Status
Exploit details are publicly available on GitHub, making this easily weaponizable. The vulnerability requires no authentication and has simple exploitation steps.
🛠️ 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 is available. D-Link has confirmed these products are end-of-life and recommends immediate retirement and replacement.
🔧 Temporary Workarounds
Disable Web Interface
linuxDisable the vulnerable CGI endpoint by removing or restricting access to /cgi-bin/apkg_mgr.cgi
rm /www/cgi-bin/apkg_mgr.cgi
chmod 000 /www/cgi-bin/apkg_mgr.cgi
Network Isolation
linuxBlock all external access to the NAS web interface using firewall rules
iptables -A INPUT -p tcp --dport 80 -j DROP
iptables -A INPUT -p tcp --dport 443 -j DROP
🧯 If You Can't Patch
- Immediately remove affected devices from internet-facing positions and isolate them in a restricted network segment
- Implement strict network access controls allowing only necessary traffic from trusted sources
🔍 How to Verify
Check if Vulnerable:
Check if the device model is in the affected list and if the /cgi-bin/apkg_mgr.cgi endpoint is accessible via HTTP POST requestsCheck Version:
Check device web interface or use command: cat /etc/versionVerify Fix Applied:
Verify the apkg_mgr.cgi file is removed or inaccessible, and test that POST requests to the endpoint no longer execute commands📡 Detection & Monitoring
Log Indicators:
- Unusual POST requests to /cgi-bin/apkg_mgr.cgi
- Suspicious command execution in system logs
- Multiple failed authentication attempts followed by successful POST requests
Network Indicators:
- HTTP POST requests to /cgi-bin/apkg_mgr.cgi with shell metacharacters in parameters
- Outbound connections from NAS to suspicious external IPs
SIEM Query:
source="nas_logs" AND (uri="/cgi-bin/apkg_mgr.cgi" AND method="POST" AND (param="f_module_name" AND value MATCHES "[;&|`$()]"))