Bitcoin fell below $79,000 on Thursday following reports of a suspected security incident at Binance, the world's largest cryptocurrency exchange. The selloff was accompanied by reports of heavy outflows from Binance-linked wallets, with some estimates citing suspicious transfers totaling up to $5.8 billion.
According to onchain data, approximately $3.55 billion in transfers moved to an unlabeled wallet. Coinbase senior director Conor Grogan cited the $5.8 billion figure in relation to the incident.
In response to the reports, major stablecoin issuers took protective measures. Tether CEO Paolo Ardoino announced the company froze more than 1.567 billion USDT. Circle froze approximately $823 million in USDC, according to former Binance CEO Changpeng Zhao, who remains a shareholder. Combined freezes ranged from $1.8 billion to $2.4 billion depending on available reports.
Binance has not issued an official confirmation of a breach. Co-founder Yi He posted on X that the company is aware of reports of a potential security issue and that security teams are actively investigating. "Users should remain cautious of scams and should not trust unofficial links, messages, or requests for account information," Yi He stated.
Changpeng Zhao, who no longer manages Binance, posted that he expects all user funds to be fully covered. "I don't manage Binance anymore, but as a shareholder, I expect all user funds will be fully covered," Zhao wrote.
Blockchain researcher Spreek flagged the suspicious activity, which reportedly included transfers through contract calls allegedly funded by Tornado Cash. Blockaid reported investigating $3.3 billion in suspicious outflows from Binance hot wallets across Ethereum, Arbitrum, and Avalanche.
If confirmed, the incident would represent the largest cryptocurrency theft on record, surpassing the February 2025 Bybit hack of approximately $1.5 billion. Aave reportedly froze lending markets to prevent the suspected attacker from borrowing.
Bitcoin traded at $78,800, down 2.89 percent over the previous 24 hours. The cryptocurrency hit a 24-hour high of $81,890 before sliding sharply after 4 p.m. ET to a low of $78,177.37 when hack rumors circulated. Trading volume reached approximately $26.14 billion, with Bitcoin's market cap at roughly $1.58 trillion.
Binance.US stated the incident does not affect its platform. Bybit confirmed its systems are operating normally with trading and withdrawals available.
Neither Binance nor law enforcement has released a formal account of the cause, and figures remain subject to revision.
