Likely dynamic fee hook on Ethereum

Uniswap v4 Hook Contract 0xf2904c057d7ba833ee015af9198ecf008a174080 on Ethereum · Dynamic fee

Volume (24h)
$28
Value locked (TVL)
$0
All-time volume
$28
Pools using this hook
1
Swaps (24h)
4 (4 traders)
Total swaps
4

What it does

This hook runs custom logic before each swap, but without verified source its effect on trader fees could not be confirmed, so it is unclear whether swaps pay more or less.

This read was written for the hook 0x30b8…0080 on Ethereum and reused here: the two share a code shape, so constants such as fees, owners and addresses can differ.

How it works step by step

  • Implements only a beforeSwap callback, which is the single enabled hook permission
  • Exposes one dispatched function, beforeSwap, taking the sender, pool key, swap params and hook data
  • Contains no storage layout, so no persistent state or configurable parameters were detected in the bytecode
  • Makes no external calls apart from the Panic(uint256) revert path, indicating only internal arithmetic checks
Swap behaviour
Runs logic before each swap in the pool; the exact fee or adjustment computed cannot be fully determined from decoded bytecode alone.
Liquidity behaviour
No liquidity callbacks.
Fee behaviour
Likely overrides the swap fee per swap via beforeSwap, but the fee computation could not be confirmed from the decoded bytecode without verified source.
Owner & admin controls
No admin controls found.

Enabled Uniswap v4 callbacks

beforeSwap

beforeSwap is enabled and used to run custom logic before each swap, which is the basis for any dynamic fee or swap gating.

Security & trust assessment

Risk level: medium, estimated (decoded bytecode, low confidence).

Who controls it: No privileged key was identified in the decoded bytecode, so no admin could change behaviour; this conclusion is limited by the lack of verified source.

Risk to user funds: The hook has beforeSwap only and no return-delta permissions were detected, so it does not appear to take custody of or move pool tokens directly; it can only influence swap pricing or revert swaps.

Security findings

  • [medium] Unverified source: No verified source is available, so the exact fee logic and any gating conditions in beforeSwap cannot be audited.
  • [info] Pre-swap logic can alter pricing: Because beforeSwap is enabled, the hook runs on every swap and may change the fee applied to traders, which affects execution cost.
  • [info] No storage detected: The inferred storage layout is empty, suggesting no owner, pause flag or tunable parameters are stored on-chain.

Contract details

Verified source
No
Bytecode size
1,049 bytes
Upgradeable proxy
No

Pools using Likely dynamic fee hook