DeFi community discussions on September 21, 2026 cover Cardano's low DeFi audit score of 51.3/100 compared to Ethereum's 96.3, collaborations on Hedera's DeFi platforms, and concerns about malicious hooks in Uniswap v4 where 54% of analyzed hooks were identified as potentially harmful.
A security researcher highlights vulnerabilities in Uniswap's approval process, demonstrating how a malicious hook extracted 4.8% of a transaction's value from a swap routed through the platform's API, illustrating risks when aggregators cannot adequately filter or validate hooks.