undetected

adj

1. Not found; undiscovered.

   “Children are an increasingly attractive target for ID thieves, in part because they're easy prey for smooth-talking predators in chat rooms, and because the crime can go undetected for years.”

   “For example, positive obstacles such as fallen trees directly along the prescribed path would high-center the vehicle and negative obstacles such as culverts near certain intersections in the Urban course went undetected and became hazards for the XUV.”