By Kim Yoo-chul
KT said Thursday that details about more than 70 percent of its clients have been stolen and sold to local mobile-phone sellers.
The hackers are believed to have stolen phone numbers, email addresses, names, jobs and bank account numbers, according to police.
“We believe details of more than 12 million customers were stolen and illegally used by unnamed third-parties,” KT said in a statement.
It added it was monitoring the situation closely.
Spokesman Kim Dong-woo said, “KT was collaborating with the Incheon Metropolitan Police Agency and will do our best to minimize the damage”
The agency has applied to prosecutors for arrest warrants for two “professional hackers” — identified only as Kim and Jeong — for allegedly stealing the data.
The attacks targeted the main homepage of the company, which is based in Bundang, Gyeonggi Province.
“Since February of last year, the hackers have been using Pharos, the very latest hacking program,” Kim said.
A police officer said, “They stole between 200,000 and 300,000 customers’ details every day. The stolen data was used to open new mobile accounts and to sell mobile devices.”
The officer said the hackers illegally earned about 11 billion won.
The scandal follows several recent cyber attacks targeting leading banks, finance companies and the government.
In April, hackers stole data from a government bank.
Information on more than 1.8 million customers was also stolen from Hyundai Capital.
KT officials said the company’s legal team was preparing for possible class-action lawsuits
“We are preparing for all possible scenarios as the incident may become a legal issue,” said an executive, who asked not to be named.
A Seoul court recently ordered SK Communications, an SK Group content affilate, to compensate users of the Cyworld and Nate websites after data on 35 million customers were stolen.