1. A system, comprising: a memory having computer readable instructions; and a processor for executing the computer readable instructions, the computer readable instructions including: receiving application code and instrumenting the application code by inserting instrumentation hooks at internal module input points, external module input points and external module release points of the application code; mapping data flow between the external module release points and the internal module input points of the application code via the instrumentation hooks; determining at least one of the internal module input points is accessible via at least one of the external module release points; and testing the accessible internal module input point by sending a test value based on a constraint to the accessible internal module input point.