Hackers attacked the hot wallet of crypto exchange HTX (formerly Huobi) on September 24, and stole 5,000 Ethers valued at $7.9 million.
The suspicious transaction was first detected by the Cyver Alerts service.
The hacker then moved 1,001 ETH to another wallet.
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The HTX team migrated the hot wallet from the platform after the incident. In addition, it also sent a transaction to the hacker's wallet with a message informing him it had identified his identity.
The exchange offered him to return the funds voluntarily by October 2 in exchange for a reward of 5% of the amount. Otherwise, the platform intends to contact law enforcement.
The attack was later confirmed by Tron founder Justin Sun, who sits on the crypto exchange's advisory board.
He has assured the exchange has fully covered the losses suffered as a result of the attack and "has successfully resolved" the related issues.