The hacker exploited a reentrancy vulnerability in Rari's Fuse lending protocol, according to a tweet by smart contract analysis firm Block Sec.

According to a tweet from Blockchain security firm PeckShield, the same vulnerability has been used to attack other forks of the Compund DeFi protocol.Rari Capital acknowledged the hack, saying borrowing has been paused globally and that no further funds were at risk.Fei Protocol, which merged last December with Rari, offered to let the attacker keep $10 million of the stolen funds as a "bounty" if the remaining funds were returned.

Rari Capital suffered from a different attack in May of last year, which saw a hacker run away with $10.6 million in user funds.

This story is developing and will be updated.