Here’s what happened in crypto today
Today in crypto: Mercado Bitcoin halted deposits and withdrawals after a hack reportedly drained more than $46 million from its wallets. Binance’s emergency Bitcoin reserves fell to roughly half their pre-hack level as the exchange moved to cover $6.3 billion in losses from an attack the FBI attributed to North Korea.
Mercado Bitcoin wallets show post-hack transfers after $46M theft
Mercado Bitcoin, one of Brazil’s largest cryptocurrency exchanges, confirmed a security incident on Monday that blockchain analysts estimated drained more than $46 million from its wallets. Despite the company’s announcement that it had suspended deposits and withdrawals, addresses associated with the incident continued to receive funds for hours afterward.
Senior security engineer at Certik, Dickson Wu, published an initial post-mortem of the incident, saying 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.
“So whoever did this can also move money out of MB’s customer deposit addresses,” he wrote.
Security firms have stated the hack was carried out through standard transfers rather than a smart contract exploit.
A spokesperson for Mercado Bitcoin told Cointelegraph that customers had suffered no losses and no data had been leaked, but the company did not respond to requests for comment on the continued transfers. A data breach could also trigger notification requirements to Brazil’s data protection authority.
The hack has not yet been attributed to an organized group and remains under investigation.
Binance taps half its SAFU Bitcoin holdings, releases reserve proof
Binance’s publicly disclosed emergency Bitcoin wallet held roughly half its previous balance on Monday after the exchange tapped its user protection fund to cover losses from Thursday’s $6.3 billion hack.
The exchange confirmed a transfer of 7,499 Bitcoin (BTC) on Saturday, linking it to the partial deployment of its Secure Asset Fund for Users (SAFU).
As of Monday, the wallet held about 7,500 BTC, worth $583 million, down from about 15,000 BTC before the transfer.
Binance began reopening withdrawals in phases on Sunday and said it had replenished approximately 95% of the affected assets, up from 90% a day earlier. It continued buying the remaining, less-liquid tokens through market and over-the-counter transactions.
The exchange is using its corporate treasury, SAFU and part of its futures insurance fund to cover the losses.
FBI blames North Korea for record $6.3B Binance hack
The FBI said that the Democratic People’s Republic of Korea (North Korea) was responsible for the theft of about $6.3 billion in digital assets from cryptocurrency exchange Binance on Thursday.
The FBI said on Saturday in a news release that it refers to this specific North Korean malicious cyber activity as “TraderTraitor,” which it has most recently observed converting stolen assets mostly into Ether (ETH).
It expects these assets to be further converted, using DeFi and instant swap services, as the hackers move to more advanced laundering stages.
The FBI urged private sector entities including THORNode operators, RPC node operators, instant exchanges, DeFi services, blockchain analytics firms and other digital asset service providers to block transactions with or derived from addresses TraderTraitor actors are using to launder these stolen assets. A full list of addresses is provided on the news release.