Chainalysis reports that Bybit lost nearly $1.5 billion in ETH on February 21, 2025, making it the largest cryptocurrency heist described in the excerpt. The attack began with social engineering against cold wallet signers, causing them to sign malicious transactions that replaced a Safe multi-signature wallet implementation contract. About 401,000 ETH was rerouted to attacker-controlled addresses, then dispersed through intermediary wallets, DEXs, cross-chain bridges, BTC and DAI swaps, and a no-KYC instant swap service; Chainalysis states the TTPs and fund links are consistent with DPRK activity.