Based on the relative dynamics model of spacecraft and cluster consistency control strategy, this paper addresses the scenario where individual spacecraft controllers in a spacecraft cluster are subjected to malicious attacks, resulting in collisions among the cluster's individuals. The fault impact mechanism is analyzed using cellular automaton theory. By integrating spacecraft motion state information, cellular objects that conform to spacecraft characteristics are established, and the evolution rules of cellular automaton are determined. Within these evolution rules, fault impact weights are defined, and a vector projection method is proposed to determine these weights based on the relative positions of neighbors and their influence on individual control laws. Finally, a simulation model is established to compute the predicted fault impact levels of spacecraft individuals based on the cellular automaton model and compare them with actual fault impact results. The accuracy of the constructed fault impact model is validated using the normalized discounted cumulative gain algorithm.