DLINK DCS-5020L - Remote Code Execution (PoC)







“The DCS-5020L Wireless N Day & Night Pan/Tilt Cloud Camera is a day/night network camera that easily connects to your existing home network for remote viewing on a range of mobile devices. It features pan, tilt and digital zoom function to allow you to see a wider area with a single camera, built-in Wi-Fi extender to effortlessly expand your wireless coverage, night vision up to 5 metres, sound and motion detection for the ultimate in peace of mind, and H.264 video compression for a high-quality image.”

This walkthrough demonstrates just how easy it can be to find vulnerabilities in Internet of Things (IOT) devices. The process of finding the following command injection can be broken down into 3 steps that are more akin to a 100 point CTF challenge: download binary, run strings, trace input to system call to origin.

An attacker can escape the ‘sed’ command with a simple payload, such as ‘`touch a`’. Another example that fits is AdminID=a’`telnetd`’, which allows a user to login as “a”, which becomes the new root account:

Source: https://www.fidusinfosec.com/dlink-dcs-5030l-remote-code-execution-cve-2017-17020/