Aggregator Hooks Launch on Ethereum, Base, and Robinhood Chain
Uniswap Labs deployed aggregator hooks on October 22, routing swaps through seven external liquidity sources across Ethereum, Base, and Robinhood Chain via Uniswap-developed adapters. The deployment covers over 90% of DEX activity on the three chains, according to the company’s routing guidance updated October 16.
The move follows months of debate over hook security in Uniswap v4, which introduced third-party hooks allowing custom logic in swaps. In September, 0x published research examining 84,163 hooks across six chains, classifying 19.4% as safe, 54.2% as malicious, and 26.4% as likely malicious as of September 11. The study found that malicious hooks quote one price during quote requests but execute at a different price, with some trades receiving up to 50% less than quoted.
Hayden Adams, Uniswap founder, dismissed the criticism in a response posted September 15, calling it a “skill issue.” Dan Robinson of Paradigm countered that “0x routing made a mistake,” arguing that aggregators should vet hooks before routing rather than relying on Uniswap’s allowlist. Duncan Townsend, an 0x engineer, stated that “0x already used Uniswap’s allowlist and alleged that at least one malicious hook sat on it.”
OpenZeppelin published an audit of Uniswap’s router and periphery changes on October 8, documenting optional per-hop slippage checks that can be omitted by passing an empty maxHopSlippage array. Uniswap’s router requires manual approval for hooks using beforeSwap, afterSwap, delta-return, dynamic-fee permissions, or specified address prefixes.
External liquidity routed through adapters appears as Uniswap v4 pools and generates fees contributing to UNI burns. On Base, one hook recorded 6,516 fills and collected $143,037 in fees. On BNB Chain, another hook recorded 4,879 fills and collected $18,592 in fees.
In July, Enso investigated an Ethereum Curve USDC/USDT pool and found 129,070 successful swaps that delivered less than quoted, with a gross quote overstatement of $225,000 and an estimated attacker extraction of $34,593. Approximately 70% of 0x’s trades touch Uniswap liquidity, according to the aggregator’s own estimate.
On Robinhood Chain, 0x alleged a malicious hook extracted 4.8% on one routing leg and 1.2% of the overall trade value. Uniswap’s documentation does not confirm whether such pools are screened or whether per-hop checks apply by default.
