The radio frequency communication protocol being used by Meross MSH30Q 4.5.23 is vulnerable to replay attacks, allowing attackers to record and replay previously captured communication to execute unauthorized commands or actions (e.g., thermostat's temperature).

Meross MSH30Q 4.5.23 is vulnerable to Cleartext Transmission of Sensitive Information. During the device setup phase, the MSH30Q creates an unprotected Wi-Fi access point. In this phase, MSH30Q needs to connect to the Internet through a Wi-Fi router. This is why MSH30Q asks for the Wi-Fi network name (SSID) and the Wi-Fi network password. When the user enters the password, the transmission of the Wi-Fi password and name between the MSH30Q and mobile application is observed in the Wi-Fi network. Although the Wi-Fi password is encrypted, a part of the decryption algorithm is public so we complemented the missing parts to decrypt it.

Meross Smart Wi-Fi 2 Way Wall Switch (MSS550X), on its 3.1.3 version and before, creates an open Wi-Fi Access Point without the required security measures in its initial setup. This could allow a remote attacker to obtain the Wi-Fi SSID as well as the password configured by the user from Meross app via Http/JSON plain request.

Meross MSG100 devices before 3.2.3 allow an attacker to replay the same data or similar data (e.g., an attacker who sniffs a Close message can transmit an acceptable Open message).

Meross MSS110 devices before 1.1.24 contain a TELNET listener providing access for an undocumented admin account with a blank password.

Meross MSS110 devices through 1.1.24 contain an unauthenticated admin.htm administrative interface.