This paper presents FISSA, an open-source software tool that facilitates the building of fault injection campaigns based on well-known HDL simulation tools. The proposed solution relies on two software modules that encapsulate an existing HDL simulator. The first module generates TCL scripts to drive the simulation process and automatically inject faults according to the user's needs. The second module is dedicated to fault analysis, enabling users to assess the resilience of their design. The proposed approach allows the designers to seamlessly integrate fault injection simulations into their workflow. To demonstrate the solution's capacity, this paper proposes a case study to evaluate the robustness of a Dynamic Information Flow Tracking mechanism integrated into a RISC-V processor against different fault injection scenarios. For that purpose, a total of 360,747 simulations have been performed.