The hackers behind the $6.3bn (£4.7bn) Binance heist used bogus job interviews, malicious software and an internal AI tool, the company has revealed.

The world’s largest cryptocurrency exchange was compromised in an operation that began with an inadvertent download of malware in June, led to a recruitment scam in September, and then a raid last week of “hot wallets” where billions of dollars worth of crypto assets were taken.

The FBI has blamed North Korea for last week’s heist but the rogue state, a prolific crypto hacker, described the accusation as “absurd rhetoric” on Tuesday.

According to an update released by Binance on Tuesday, the hackers got their first foothold in the summer when a Binance engineer inadvertently…