dForce contacted the hacker via blockchain transaction, offering to negotiate a bounty. Several days later, the project tweeted that the attacker had "c[o]me forward as a whitehat", and that the funds had been fully returned. "We have agreed to offer a bounty and will drop all on-going investigation and law enforcement actions," they announced.
dForce Network exploited for $3.65 million, funds returned
An attacker using flash loans to exploit a common re-entrancy vulnerability siphoned $3.65 million from the dForce defi project on both Arbitrum and Optimism, which are Ethereum layer-2 networks. The exploit, which involves manipulating the oracle price in Curve liquidity pools, is a common one that was first reported to Curve in April 2022 and disclosed in October 2022. It has been used to attack various other projects, including QiDAO.