Moxa MGate Authentication Bypass Vulnerability

An attacker could gain administrative access to an MGate gateway without authentication, allowing them to alter protocol translation rules, reconfigure device settings, or redirect industrial protocol traffic. This could disrupt communication between control systems and field devices, leading to loss of visibility or control over plant operations.

Water utilities and electric utilities using Moxa MGate protocol gateways for SCADA communication between legacy industrial devices and modern control systems are affected. This includes MGate MB3180, MB3280, MB3480, MB3170, and MB3270 units running the affected firmware versions. Any facility using these gateways for critical process data translation between Modbus RTU/TCP and other industrial protocols should be considered at risk.

An attacker on the network would connect to the MGate's web management interface (typically port 80 or 443) and send a crafted authentication request. The improper cryptographic handling allows the attacker to bypass authentication checks and reach the administrative interface where they can modify gateway configuration and routing rules.