A record-breaking hack at Binance, the world’s largest cryptocurrency exchange, is a reminder of the risks investors take when trusting a company to hold their digital tokens.

Binance said Friday that the security breach affected about $6.3 billion in client assets, making it the largest crypto hack on record. Around $3 billion of the affected assets has been frozen on blockchain networks, and the exchange says it has begun recovering some of them.

Binance’s initial investigation suggests hackers gained access to the firm’s withdrawal systems and were able to make unauthorized transfers from the exchange’s crypto wallets, according to the company. The company says it has found no evidence that the private keys controlling those wallets…