Cybersecurity threats are rising for industrial control systems around the world, a growing target for attackers seeking to wreak havoc, a study showed Thursday. The study by Ponemon Institute and Unisys Corp of 599 technology executives in 13 countries found that even as threats are rising, organizations are not as prepared as they should be to deal with cyber attacks. The study said the risk to industrial control systems is believed to have substantially increased, with 57 percent of the respondents citing greater threats.