Brazil's Largest Exchange Mercado Bitcoin Halts Withdrawals After $40 Million Hack

Brazil's largest crypto exchange, Mercado Bitcoin, suspended deposits and withdrawals on Monday after identifying a security incident in one of its systems in the early hours of the morning. The exchange emphasized that no customer lost money and no data leaked during the breach.

Suspicious Transfers

Blockchain security firm Hypernative flagged more than $40 million in suspicious transfers that may be linked to the incident, according to a preliminary analysis spanning at least 10 blockchains including Bitcoin, Ethereum, Solana, and Tron. Mercado Bitcoin has not confirmed that figure and has not disclosed how the attackers gained access.

Tracking Funds

In a follow-up post, the exchange published the destination addresses it identified on five networks: EVM chains, Bitcoin, Solana, Stellar, and Tron. It clarified that these addresses were released only to help others identify and track the funds on-chain.

Tether CEO Paolo Ardoino confirmed that the stablecoin issuer has frozen more than 4.5 million USDT connected to the incident. USDT is a dollar-pegged stablecoin that can be blacklisted by Tether to prevent movement of tokens.

Ongoing Investigation

The incident comes days after hackers drained more than $6 billion from Binance on October 29, which the FBI attributed to North Korea's TraderTraitor group. Mercado Bitcoin has not linked the two incidents and has not identified who is behind its own breach.

Deposits and withdrawals at Mercado Bitcoin remain suspended, with no date provided for resumption. The exchange has committed to posting regular updates on X as the investigation continues.