“The big problem is that hospitals don’t buy new devices, and they keep using really dangerous ones ad infinitum — until they just stop working” — By Lindsay Gellman Last spring, Joshua Corman found himself staring in disbelief in a New Hampshire hospital. Corman, a cybersecurity researcher and self-described “good-guy hacker,” had brought his 11-year-old daughter in for blood work. After several hours of waiting, it was clear it would be a long night, so he’d…