Bent Finance was exploited by rogue developer who inserted backdoor into contracts during period lacking multisig protection, extracting 513k cvxcrv LP tokens (~440 ETH/$1.75M).

The staking and yield farming platform Bent Finance tweeted that the Bent Deployer wallet upgraded the curve pool contract from November 30, 2021 to 2021 01:09:27 PM +UTC, and the exploiter added a malicious contract that made cvxcrv and cvxcrv and The mim pool is able to hardcode user balances and then deploy another contract to mask it. The attackers stole a total of 513,000 cvxcrv LP tokens. Bent Finance later updated the incident report saying that with the help of two white hat hackers, the team analyzed the incident and concluded: "This was actually the work of an 'inside member'. After several days of hacking, the attackers finally agreed to return the funds to the following multisig address: 0xaBb8B277F49de499b902A1E09A2aCA727595b544. The attackers sold off (now bounced back) and sent us ETH and DAI, there was a slight shortfall in returning funds, but we've fixed that. So far, we have raised another 200,000 cvxcrv (~$1 million) from the community to help fill the gap. "The official said that the vulnerability has been fixed to ensure that such incidents do not occur again.