An issue was discovered on Moxa MGate MB3170 and MB3270 devices before 4.1, MB3280 and MB3480 devices before 3.1, MB3660 devices before 2.3, and MB3180 devices before 2.1. Sensitive information is sent to the web server in cleartext, which may allow an attacker to discover the credentials if they are able to observe traffic between the web browser and the server.