On July 16, 2025, BigONE crypto exchange suffered a supply chain attack where an attacker gained access to production infrastructure and modified critical backend logic to automatically approve fraudulent withdrawal requests. The attack drained approximately $27 million across five blockchains before being detected.

According to monitoring by the SlowMist security team, cryptocurrency exchange BigONE has suffered a supply chain attack, with losses exceeding $27 million. The attacker breached the production network and altered the operating logic of servers related to account management and risk control, enabling unauthorized fund withdrawals. Notably, no private keys were leaked in this incident.