CVE-2014-125117
📋 TL;DR
This critical vulnerability allows unauthenticated attackers to execute arbitrary code with system privileges on affected D-Link devices by sending a specially crafted HTTP POST request. The stack-based buffer overflow in the my_cgi.cgi component affects D-Link DSP-W215 and potentially other models, enabling complete device compromise. Anyone using vulnerable D-Link devices with internet exposure is at immediate risk.
💻 Affected Systems
- D-Link DSP-W215 Smart Plug
- Other D-Link devices using similar my_cgi.cgi component
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete device takeover allowing attacker to install persistent malware, pivot to internal networks, intercept all network traffic, or brick the device permanently.
Likely Case
Remote code execution leading to botnet enrollment, credential theft, network surveillance, or use as a proxy for further attacks.
If Mitigated
Limited impact if device is isolated behind strict firewall rules with no internet exposure and network segmentation.
🎯 Exploit Status
Metasploit module available, making exploitation trivial for attackers with basic skills.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: No official vendor advisory found
Restart Required: No
Instructions:
No official patch available. Consider device replacement or network isolation as primary remediation.
🔧 Temporary Workarounds
Network Isolation
linuxBlock all external access to the device and restrict internal access to trusted networks 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
Endpoint Blocking
linuxBlock access to the vulnerable /common/info.cgi endpoint at the web server or firewall level.
iptables -A INPUT -p tcp --dport 80 -m string --string "/common/info.cgi" --algo bm -j DROP
🧯 If You Can't Patch
- Immediately disconnect vulnerable devices from internet-facing networks
- Implement strict network segmentation to isolate affected devices from critical systems
🔍 How to Verify
Check if Vulnerable:
Check device model and firmware version via web interface or by examining HTTP responses from the device.Check Version:
curl -s http://device-ip/common/info.cgi | grep -i version || check web interface at http://device-ipVerify Fix Applied:
Since no patch exists, verify workarounds by testing that /common/info.cgi endpoint is inaccessible and device is isolated.📡 Detection & Monitoring
Log Indicators:
- Unusual POST requests to /common/info.cgi
- Large payloads in HTTP requests to the device
- Multiple failed exploit attempts
Network Indicators:
- HTTP POST requests to /common/info.cgi with oversized parameters
- Unusual outbound connections from the device
- Shellcode patterns in HTTP traffic
SIEM Query:
source="firewall" AND dest_port=80 AND uri_path="/common/info.cgi" AND http_method="POST" AND (content_length>1000 OR contains(content,"\x90\x90\x90"))🔗 References
- https://raw.githubusercontent.com/rapid7/metasploit-framework/master/modules/exploits/linux/http/dlink_dspw215_info_cgi_bof.rb
- https://web.archive.org/web/20140525215526/http://www.devttys0.com/2014/05/hacking-the-dspw215-again/
- https://www.exploit-db.com/exploits/34063
- https://www.fortiguard.com/encyclopedia/ips/38932/d-link-info-cgi-post-request-buffer-overflow
- https://www.vulncheck.com/advisories/dlink-stack-based-buffer-overflow-rce
