With increasing autonomous features of vehicles, key issues of robotic- and automotive engineering converge toward each other. Closing existing security gaps of device communication networks will be an enabling feature for connecting autonomously interacting systems in a more secure way. We introduce a novel approach for deriving a secret key using a lightweight cipher in the firmware of a low-end control unit. In this approach, we propose to use a non-standardized lightweight algorithm with unique hardware based parameters to prevent duplicate key generation. The randomness of the selected cipher was assessed by applying the NIST statistical test suite to produced key values. By evaluating the method on a typical low-end automotive platform, we could demonstrate the realistic applicability of the solution. The proposed method counteracts a known security issue in device communication between control units not only present in automotive solutions but also in the robotics domain. The security of the implemented solution has been compared to current automotive guidelines and recommendations for the security of resource constrained devices, also present in robotics. This approach allows low-end communication systems to be enhanced by message- and device authentication.