Binance said Friday that a security incident had an estimated impact of $6.3 billion. The exchange said about $3 billion in cryptocurrency assets have been frozen so far, and it pledged to cover all losses.
Binance said its initial investigation suggests "the security incident may involve a compromised DevOps engineer's laptop, which allowed an attacker to gain access to a service container and submit unauthorized withdrawal transactions." The company also said it found no evidence of a wallet private key leak.
Binance co-founder Yi He said deposits remained unaffected and the exchange continued to operate normally. Binance expects to begin resuming withdrawal services within 48 hours. It temporarily suspended deposits and withdrawals, revoked the affected address authorization, and enlisted law enforcement and blockchain intelligence firms to trace and recover funds.
Binance said it would cover losses using its Secure Asset Fund for Users and company funds. It also said it would publish a technical report and an updated Proof of Reserves after remediation.
Circle Internet Group, Tether and Ripple moved to freeze funds tied to the hack. Circle CEO Jeremy Allaire said the company had frozen more than $800 million in USD Coin associated with the incident. Tether CEO Paolo Ardoino said his firm had frozen more than $1.5 billion of its stablecoin that may have been related to a potential breach. Ripple said it was actively freezing affected funds held in RLUSD. Yi He later said Ripple helped halt the movement of $200 million in funds linked to the possible attack.
Crypto data provider Arkham Intelligence linked nearly $6 billion in digital assets to 55 wallet addresses it associates with the potential exploit. Arkham said it identifies and flags wallets by analyzing publicly available blockchain data and by soliciting tips from its community.
Bitcoin fell more than 4% to $77,994.96 on Friday. Shares of Circle tumbled about 5% in after-hours trading on Thursday.