South Korean crypto exchange GDAC has been hacked for approximately $13.9 million worth of crypto. The exchange has halted all deposits and withdrawals and is performing emergency server maintenance in response to the attack, according to an April 10 announcement from GDAC CEO Han Seunghwan.

According to the announcement, the attacker gained control of some of the exchange’s hot wallets on the morning of April 9, and at 7 a.m. Korean Standard Time began moving crypto into wallets under the attacker’s control. Around 61 Bitcoin (BTC), 350.5 Ether (ETH), 10 million of the WEMIX gaming currency, and $220,000 worth of Tether (USDT) were stolen in the attack. This totals around $13.9 million worth of crypto at April 10 prices.

The amount stolen is “approximately 23% of Gdac’s current total custodial assets,” the announcement said. The exchange has alerted the police, reported the hack to the Korea Internet & Security Agency (KISA), and notified the Financial Intelligence Unit (FIU) of the loss caused by the attack.

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GDAC is also asking crypto exchanges not to honor deposits made from the address that performed the attack.

Seunghwan said that the exchange does not know when withdrawals will be resumed. “We ask for your understanding that it is difficult to confirm the resumption point of deposit and withdrawal as the investigation is currently underway,” he said, according to Google Translate.

Centralized exchange hacks continue to be a problem in the crypto industry. Case in point: Crypto.com was hacked for over $15 million in January 2022. Amid a liquidity crisis at FTX, an attacker drained $663 million from the failed crypto exchange. The GDAC attack may be the first major centralized crypto exchange hack of 2023.