Moxa OnCell G3100-HSPA Series version 1.6 Build 17100315 and prior use a proprietary monitoring protocol that does not provide confidentiality, integrity, and authenticity security controls. All information is sent in plain text, and can be intercepted and modified. The protocol is vulnerable to remote unauthenticated disclosure of sensitive information, including the administrator's password. Under certain conditions, it's also possible to retrieve additional information, such as content of HTTP requests to the device, or the previously used password, due to memory leakages.