Contact Graph Routing (CGR), later standardized as Schedule-Aware Bundle Routing (SABR) by the Consultative Committee for Space Data Systems (CCSDS), is commonly implemented through modifications of Dijkstra and Yen's algorithms. The contribution of this paper lies in the detailed analysis and measurement of the effects caused by Yen's algorithm on CGR. It is observed that Yen's algorithm significantly reduces the scalability of CGR, rendering it unsuitable for scenarios involving numerous nodes numbering in the thousands or even hundreds. Furthermore, our analysis sheds light on how Yen's algorithm introduces unpredictable performance in CGR, resulting in substantial variations in memory usage and processing demands during the scheduling of individual bundles. This critical examination of the algorithm's behavior highlights operational risks, as potential adversaries could exploit this vulnerability by strategically forging and transmitting only a few bundles, effectively paralyzing the network.