Mercado Bitcoin confirms $46 million hack, stablecoin issuers freeze funds

Mercado Bitcoin , recognized as one of Brazil’s largest cryptocurrency exchanges, reported a security breach resulting in over $46 million siphoned from its wallets on Monday. Despite the company’s immediate suspension of deposits and withdrawals, cryptocurrency addresses linked to the incident continued to process transactions for several hours following the announcement. Cybersecurity firms indicated the perpetrators conducted the theft through conventional transfers rather than exploiting vulnerabilities in smart contracts. Analysts identified that the attackers methodically targeted eight less prominent blockchains, including Base, Optimism, and Arbitrum, over a four-hour window before moving on to Mercado Bitcoin’s main hot wallets.