According to CoinMeta, the founder of onekey stated in an interview with Binance that the theft of $1.5 billion from bybit was not due to multi-signature contracts, cold wallets, or vulnerabilities in ledger itself. Instead, it was caused by a social engineering attack on the front-end engineers of safe, which resulted in malicious code being implanted into the official website's front-end. The signatories saw a normal transfer interface but actually signed transactions that transferred contract permissions via delegatecall to safe, ultimately leading to the theft of assets.