“I can absolutely make a big traffic problem all over the world,” the hacker said. On some cars, the software has the capability of remotely turning off the engines of vehicles that are stopped or are traveling 12 miles per hour or slower, according to the manufacturer of certain GPS tracking devices. By reverse engineering ProTrack and iTrack’s Android apps, L&M said he realized that all customers are given a default password of 123456 when they sign up. ProTrack is made by iTryBrand Technology, a company based in Shenzhen, China. iTrack is made by SEEWORLD, a company based in Guangzhou,...