Brazil’s leading cryptocurrency platform, Mercado Bitcoin, announced on Monday that it has temporarily suspended both deposits and withdrawals after detecting a security incident in one of its systems during the early hours of the day.
In a statement posted on X, the exchange said the incident was quickly contained and that no customer funds were compromised and no data was leaked. As a precautionary measure, the platform halted all inbound and outbound transactions while it investigates the breach.
Potential Scale of the Attack
Blockchain security firm Hypernative reported that more than $40 million in suspicious transfers may be linked to the incident. The preliminary analysis identified activity on at least ten blockchains, including Bitcoin, Ethereum, Solana, Tron, and others. Mercado Bitcoin has not confirmed the amount or disclosed how the attackers accessed its systems.
The exchange later published a list of destination addresses on five networks—EVM chains, Bitcoin, Solana, Stellar and Tron—to enable the community to monitor the movement of the funds.
Tether’s Response
Paolo Ardoino, CEO of stablecoin issuer Tether, said the company has frozen more than 4.5 million USDT associated with the incident. The freeze prevents the tokens from being moved, though it does not automatically return the assets to their owners.
Context and Outlook
The breach follows a recent high‑profile hack of Binance, where over $6 billion was stolen. Mercado Bitcoin has not linked the two events and has not identified the perpetrators.
Deposits and withdrawals remain suspended, and the exchange has not provided a timeline for resuming services. It pledged to issue regular updates on X.
