Bithumb, one of the largest cryptocurrency exchanges in the world, has been hacked to the tune of 35 billion won, according to Yonhap News. This figure is equal to about $31.6 million.
Bithumb urgently ask our valuable customers not to deposit any fund into Bithumb wallet addresses for the time being.
— Bithumb (@BithumbOfficial) June 20, 2018
The exchange suspended all deposits at approximately 00:53 UTC and began transferring large amounts of Ethereum into cold wallets (digital wallets which are not connected to the internet). Ripple was reportedly among the denominations stolen.
According to local news outlet JoongAng Daily, the exchange performed an “urgent” security check on the 16th of the month, specifically preparing to move passwords to a cold wallet in preparation for an attack. The actual hack took place on the 19th, according to CoinTelegraph Japan which cites hack detection service Sentinel Protocol.
The exchange has undertaken to repay customers from its own pocket, according to JoongAng Daily. “If you have any damage to your password, I will make full compensation to your company. I do not have any damage to you, so please do not be anxious,” said Bithumb (translated from Korean).
Bithumb was also hacked in July 2017, when the personal data of 30,000 customers was stolen. The thieves used this information to access money in many people’s accounts.
Despite this, the exchange saw its profits grow by 171 percent over the year 2017. In April 2018 it was handling around $200 million worth of cryptocurrency trading a day, and today that figure is $400 million, making it the sixth biggest cryptocurrency exchange in the world.
In January it partnered with the a major shopping mall in South Korea, enabling cryptocurrency payments at outlets on the site. In March it announced plans introduce Bitcoin ATMs and Bitcoin payments at food kiosks via a partnership with some local kiosk manufacturers.