Korea’s largest crypto exchange Upbit suffered a massive hacking attack Thursday, resulting in the loss of over 44 billion won ($30.1 million) in assets, the exchange operator said.
In a notice to customers, Dunamu said it confirmed the transfer of 44.5 billion won worth of Solana-affiliated assets to an unauthorized wallet address at 4:42 a.m. and plans to cover the full amount with assets the company owns.
Earlier in the day, the company said the total damage amounted to 54 billion won, but later revised the amount based on the price of the affected assets at the time of the incident.
“The attack occurred on the ‘hot wallet’ operated by Upbit and no security breaches or extortion of assets happened with our cold wallets,” the exchange operator said.
Hot wallets store virtual assets online, while cold wallets store assets offline.
As a follow-up measure, Dunamu said it has temporarily suspended virtual asset deposit and withdrawal services and is conducting a comprehensive security review.
It also initiated an on-chain freezing measure, successfully freezing around 2.3 billion won worth of Solayer token assets. Solayer, or SOL, are native tokens that are traded on the Solana network.
“We are tracking the rest of the assets and are working with related projects and institutions to conduct additional asset freezing,” the exchange operator said.
Financial authorities have also launched an on-site inspection to assess the situation.
The incident is the largest security breach at Upbit in six years, after some 340,000 Ethereum tokens worth 58 billion won were illicitly transferred to an anonymous account on Nov. 27, 2019. Upbit is the country’s largest and the world’s fourth-largest crypto exchange in terms of trading volume.
It also came on the day the cryptocurrency exchange held a joint press conference with portal operator Naver Corp. and its fintech arm Naver Financial Corp. on their merger deal expected to create a fintech company worth 20 trillion won.
Shares of Naver fell 4.6 percent to 251,500 won at the market close.
