Mobile manipulation will play an essential role in future production’s intralogistics. In addition, it can be assumed that location-independence of manipulation will greatly contribute to flexible production and higher efficiency in robot use. Modular mobile manipulators can be combined from standalone robotic components like mobile platforms and serial arms. This combination enables more flexibility since the robot can be adapted to specific use-cases by exchanging hardware. However, since those robots tend to be very complex systems, their integration into networked Industry 4.0 environments will also cause security risks. In this paper, we present a security architecture and secure interaction workflows for modular mobile manipulators that on the one hand secure the system against unauthorized manipulation and on the other hand enable the integration of mobile manipulators into larger IT infrastructures. Using the example of our inhouse-developed CHIMERA mobile manipulator, we show which architectural means can be considered in order to make a modular mobile manipulator secure. We analyze the expected attack vectors on mobile manipulators and describe their mitigation within our architecture.