Bithumb, a bitcoin and ether exchange based in South Korea, suffered a major security breach last week which resulted in a number of user accounts getting compromised and monetary losses running into thousands of dollars, Brave New Coin reported.

Quoting local newspaper source Kyunghyang Shinmun, Brave New Coin stated that according to a survey of the users affected by the hack "it is estimated that hundreds of millions of won have been withdrawn from accounts of one hundred investors. One member claims to have had 1.2 billion won stolen."

The breach took place on June 29 with hackers getting their hands on the personal information of 31,800 Bithumb users, which included their names, mobile phone numbers, and email addresses. The exchange reported the incident to the authorities on June 30. It claims to have reported the hack to the Korea Communications Commission, the Korea Internet & Security Agency (KISA), and the Supreme Prosecutors' Office.

While Bithumb admitted the incident, it maintains that the attackers could not get a direct access to funds stored on its platform. It claims that hack was made to an employee’s personal computer, not the exchange’s internal network.

“The employee PC, not the head office server, was hacked. Personal information such as mobile phone and email address of some users were leaked. However, some customers were found to have been stolen from because of the disposable password used in electronic financial transactions”, Bithumb said, as quoted by BNC.

While victim accounts differed on how the funds were stolen, hackers appear to have gotten hold of user credentials and used “voice phishing” – a process in which hackers call victims posing as the exchange’s representatives – to steal the funds.

In an official notice, Bithumb stated that the "compensation for personal information leakage cases has been decided." It would pay up to 100,000 won per person (approximately US$870) to members, adding that it would compensate further damages as soon as the amount is confirmed.

Over 100 affected users have filed a complaint with the National Police Agency's cybercrime report center. According to the Herald, victims are also expected to file a class action lawsuit against the exchange.

FxWirePro launches Absolute Return Managed Program. For more details, visit http://www.fxwirepro.com/invest