Your Smart Watch Can Steal Your ATM PIN. From IEEE Spectrum. Mobile systems and cyber security expert Yan Wang doesn’t wear a smart watch.“It knows too much,” says Wang, an assistant professor of computer science at Binghamton University in Upstate New York. “If you are using a smart watch, you need to be cautious.” He would know. Wearable devices can give away your PIN number, according to research he and colleagues presented in June at the 11th annual Association for Computing Machinery Asia Conference on Computer and Communications Security (ASIACCS) in Xi’an, China. By combining smart watch sensor data with an algorithm to infer key entry sequences from even the smallest of hand movements, the team was able to crack private ATM PINs with 80 percent accuracy on the first try and more than 90 percent accuracy after three tries.