Abstract. The requirement for higher security and dependability of systems is continuously increasing even in domains not traditionally deeply involved in such issues. Yet, evolution of embedded systems towards devices connected via Internet, wireless communication or other interfaces requires a reconsideration of secure and trusted embedded systems engineering processes. In this paper, we propose an approach that associates model driven engineering (MDE) and formal validation to build security and dependability (S&D) patterns for trusted RCES applications. The contribution of this work is twofold. On the one hand, we use model-based techniques to capture a set of artifacts to encode S&D patterns. On the other hand, we introduce a set of artifacts for the formal validation of these patterns in order to guarantee their correctness. The formal validation in turn follows the the MDE process and thus links concrete validation results to the S&D requirements identified at higher levels of abstraction.