eQ-3 Homematic CCU2 and CCU3 with the XML-API through 1.2.0 AddOn installed allow Remote Code Execution by unauthenticated attackers with access to the web interface, because the undocumented addons/xmlapi/exec.cgi script uses CMD_EXEC to execute TCL code from a POST request.
eQ-3 Homematic CCU2 and CCU3 with the CUxD AddOn installed allow Remote Code Execution by unauthenticated attackers with access to the web interface, because this interface can access the CMD_EXEC virtual device type 28.
eQ-3 Homematic CCU2 and CCU3 with the CUxD AddOn before 2.3.0 installed allow administrative operations by unauthenticated attackers with access to the web interface, because features such as File-Browser and Shell Command (as well as "Set root password") are exposed.