Mercado Bitcoin, Brazil’s largest cryptocurrency exchange, began a phased reopening of customer access on Monday, one week after a security breach drained $48.6 million from its wallets. The exchange confirmed on X that account logins were being restored gradually, with web access opening from 16:00 local time and reaching all Mercado Bitcoin customers by 18:00. For now, users can only view their total balance, net worth, and investments by category and asset; trading, deposits, withdrawals, transfers, MB card services, Pix and TED payments remain unavailable.
According to an updated help-center FAQ, the exchange is validating each restoration phase with security checks. New account signups and API access are still offline. When withdrawals return, Pix withdrawals will initially be limited to accounts held under the customer’s own name and CPF tax ID. Every user will also need to revalidate registration details and set a new password before accessing funds. The balances displayed reflect account positions on November 2, the day of the attack, before the breach occurred.
Mercado Bitcoin says customers will not lose funds and plans to cover the missing coins using its own money. Fabrício Tota, vice president of new business, said in a video posted November 5 that the company is already buying crypto through partners in Brazil and abroad to rebuild reserves. The exchange is relying on roughly $300 million raised since its founding, including a $20 million investment from Tether in July. More than 33% of the stolen funds have reportedly been frozen, and the unrecovered portion amounts to about 3% of Mercado Bitcoin’s total custody. Tota estimated the hacker still holds roughly $33 million.
Blockchain tracing by Bitquery found that $48.6 million left Mercado Bitcoin across 11 blockchains on November 2. The attacker was able to sign for customer deposit addresses and emptied 36,042 addresses on Ethereum. The attack continued for about four hours after the exchange said it had been contained. Stablecoin issuers, led by Tether, Circle and Paxos, froze about $11.8 million of the stolen funds. The incident follows a massive $6.3 billion theft from Binance on October 29; BitMart was also hit that same day, and its founder Sheldon Xia has said one group is responsible for all of these attacks.
