An Use of Hard-coded Credentials vulnerability has been identified in Moxa’s network security appliances and routers. The system employs a hard-coded secret key to sign JSON Web Tokens (JWT) used for authentication. This insecure implementation allows an unauthenticated attacker to forge valid tokens, thereby bypassing authentication controls and impersonating any user. Exploitation of this vulnerability can result in complete system compromise, enabling unauthorized access, data theft, and full administrative control over the affected device. While successful exploitation can severely impact the confidentiality, integrity, and availability of the affected device itself, there is no loss of confidentiality or integrity within any subsequent systems.