Cyber-Physical Systems (CPS) are commonly supervisory controlsystems where a human-on-the-loop (HOL) supervises one or moreautonomous systems, while embedded autonomy allows the operatorsto intermittently attend to the system and other tasks. Thus,it is imperative that the design of any security-aware CPS considersthe impact of the human interaction with the system onsecurity guarantees. Yet, there has been very little work on designof Human-CPS that promotes human situational awareness for enhancedsystem performance, particularly in terms of cyber-physicalsecurity and real-time defense against attacks. One of the mainobstacles to the rapid advancement of this field is the scarcity oftestbeds for evaluating security-aware Human-CPS interactions.We present RESCHU-SA, an extendable virtual platform thatfacilitates studying the impact that HOL has on security of CPSwith varying levels of autonomy. It allows users to analyze howinductive reasoning and ability to provide context, particularlyduring an attack, affects the overall CPS security guarantees. Theproposed platform is an extension of the Research Environmentfor Supervisory Control of Heterogeneous Unmanned Vehicles(RESCHU) simulation environment, previously used in variousapplications including studies focused on supervising UnmannedAerial Vehicles (UAVs) missions and evaluation of interface usability.