An exploitable authenticated command-injection vulnerability exists in the web server functionality of Moxa NPort W2x50A products with firmware before 2.2 Build_18082311. A specially crafted HTTP POST request to /goform/net_WebPingGetValue can result in running OS commands as the root user. This is similar to CVE-2017-12120.
http://seclists.org/fulldisclosure/2018/Nov/64
http://packetstormsecurity.com/files/150535/Moxa-NPort-W2x50A-2.1-OS-Command-Injection.html