Mercado Bitcoin wallets keep moving funds after $46M hack

Mercado Bitcoin, one of Brazil’s largest Bitcoin exchange, has confirmed a security incident that saw over $46 million worth of cryptocurrency drained from wallets on Monday. Despite the company’s announcement that deposits and withdrawals had been suspended, addresses associated with the incident continued to receive funds for hours afterward.

Security firms have stated the hack was carried out through standard transfers, rather than a smart contract exploit.

Senior security engineer at Certik, Dickson Wu published an initial post mortem of the incident, stating that the attackers “picked at eight small chains for four hours,” including Base, Optimism and Arbitrum. The attack then moved to the company’s main hot wallets before transferring tiny amounts of Ether (ETH) from 27,160 different addresses.