Crypto exchange BigONE hacked for over $27 million in hot wallet exploit

Seychelles-based crypto exchange BigONE announced Wednesday that it lost $27 million due to a security attack.

"In the early hours of July 16, BigONE detected abnormal movements … Upon investigation, it was confirmed to be the result of a third-party attack targeting our hot wallet," BigONE said in its announcement.

According to the official statement, the crypto exchange lost 120 BTC, 350 ETH, 1,800 SOL and around 8.54 million USDT across four different networks. It also lost funds in eight different cryptocurrencies, including DOGE, SHIB and CELR.

Blockchain security firm SlowMist reported the incident earlier on Wednesday, stating that the exchange's supply chain had been attacked.

Supply chain attacks happen when a hacker enters and modifies software by injecting their malicious code into a system. The code inserts can be employed to deliver a malicious payload or backdoor malware. 

"The production network was compromised, and the operating logic of account and risk control-related servers was modified, enabling the attacker to withdraw funds," SlowMist wrote in its X post. "Notably, the private keys were not leaked.​"

Aligned with SlowMist's earlier report, BigONE said that all private keys to the exchange's wallets are safe and that it has identified the attack path to prevent further losses. BigONE added that it is working with SlowMist to track the hacker and the movement of funds.

"BigONE will fully cover all losses incurred from this incident," the exchange said, adding that it has activated its internal security reserves to stabilize its liquidity pools, with deposit and trading services expected to resume in the coming hours.

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