Binance.US has so far had no issues with security. However, the global site was hacked in 2019 for the sum of 7,000 BTC, roughly equivalent to $40 million. It should be reassuring for potential traders to know that Binance says it paid affected users back in full. Fiat currencies held on Binance are insured by the FDIC for up to $250k (through custodial accounts), though cryptocurrencies are not.