A new finding from 0x is spotlighting a different kind of risk in Uniswap v4, a risk that sits not at the smart contract layer but at the interface used to trade. 0x scanned more than 84,000 Uniswap v4 hooks across 6 chains and found that over half were classified as malicious.
Here’s how it works: hooks, custom contracts that change how pools behave, can present an attractive quote when a wallet or aggregator asks for a price. But, when the trade actually settles, the outcome for the user can be much worse. In some of the worst cases, 0x said users got up to 50% less than quoted.
0x’s research shows just 19.4% of hooks looked safe, with the rest either malicious or suspected malicious.
This is bigger than an isolated exploit. Most traders rely on third-party interfaces to find the best route, not on manually checking every pool contract. If a pool can advertise one price and deliver another, the real challenge is whether routing systems are screening out bad actors or just racing to show the best headline quote.
For now, the key risk is interface trust: the best quote seen on Uniswap v4 is not necessarily the trade that gets delivered.