This work-in-progress paper introduces a prototype for a novel Graph Neural Network (GNN) based approach to estimate hidden states in cyber attack simulations. Utilizing the Meta Attack Language (MAL) in conjunction with Relational Dynamic Decision Language (RDDL) conformant simulations, our framework aims to map the intricate complexity of cyber attacks with a vast number of possible vectors in the simulations. While the prototype is yet to be completed and validated, we discuss its foundational concepts, the architecture, and the potential implications for the field of computer security.