A vulnerability has been discovered in Moxa MGate which allows an attacker to perform a man-in-the-middle (MITM) attack on the device. This affects MGate MB3170 Series Firmware Version 4.2 or lower. and MGate MB3270 Series Firmware Version 4.2 or lower. and MGate MB3280 Series Firmware Version 4.1 or lower. and MGate MB3480 Series Firmware Version 3.2 or lower.

Moxa MGate MB3180 before 1.8, MGate MB3280 before 2.7, MGate MB3480 before 2.6, MGate MB3170 before 2.5, and MGate MB3270 before 2.7 use weak encryption, which allows remote attackers to bypass authentication via a brute-force series of guesses for a parameter value.