Shenzhen Aitemi M300 Wi-Fi Repeater (hardware model MT02) contains an unauthenticated OS command injection vulnerability that allows network-adjacent attackers to execute arbitrary shell commands by injecting unsanitized input through the smacfilter_conf handler in the commuos web backend. Attackers can append semicolon-delimited payloads to the name, enable, or mac GET parameters, which are passed without sanitization into sprintf() to build uci shell commands executed via doSystemCmdComlib(), granting full root-level control of the device.