The information subtracted and later sold includes the names, DNI numbers, place of work and banking information of the affected clients, which represent three quarters of KT’s users, said the Metropolitan Police Agency of Incheon, a city west of Seoul.
The two hackers, aged 29 and 38, identified by their last names as Kim and Jung, respectively, hacked into the South Korean telecommunication company’s computer system using a program they developed, said the police report. This program allowed them to extract the clients’ information by randomly inserting 9-digit verification numbers, according to the authorities.
The police think the suspects, who have been arrested along with a third person also allegedly involved, started stealing information on February and got up to 300,000 files in a single day. According to the police report, that would have made them around 11,500 million Won (7.86 million Euro) using the stolen information to sell mobile devices.
Data leaking is a sensitive subject in South Korea since the personal and banking profiles of nearly 20 million people fell in the wrong hands on January, representing almost all clients of the nation’s main banking institutions.