Bybit, the world's second-largest cryptocurrency exchange, has suffered a record-breaking hack, losing $1.46 billion (approximately 1.1 trillion won). This surpasses the 2014 Mt. Gox incident ($470 million) and the 2021 Poly Network incident ($611 million).

Bybit CEO Ben Zhou announced on February 21 (local time) that "a hacker attacked one of Bybit's wallets" and "stole Ethereum and other ERC-20 based cryptocurrencies."

Cryptocurrency wallets encrypt private keys to enhance security. They are categorized into 'cold wallets' (offline) and 'hot wallets' (online) depending on the key storage method. Exchanges typically store 70-80% of user assets in cold wallets, which offer higher security, and the remainder in hot wallets for faster deposits and withdrawals.

However, any type of wallet requires internet access for asset transfers, and cold wallets are not immune to hacking. Bybit was attacked while transferring Ethereum, equivalent to about 9% of its total assets, from a cold wallet to a warm wallet.

The main suspect in this incident is the North Korean hacking group Lazarus, which was also responsible for the 2019 Upbit hack. Arkham Intelligence stated that "analyst ZachXBT has submitted evidence that Lazarus is the culprit."

Hwang Seok-jin, a professor at Dongguk University's Graduate School of International Information Protection, said, "It is a realistic alternative for users to distribute their assets across different exchanges" and "domestic exchanges should strengthen their security and authorities should conduct regular security checks on exchanges in the wake of the Bybit hack."