Alchemix Transmuter
Alchemix
DeFiFoundrySolidity
16,653 OP
View results
Previous Next
Submission Details
Severity: low
Invalid

Improper Enforcement of Premium Price in _swapUnderlyingToAsset() on StrategyOp.sol, StrategyArb.sol contracts and the claimAndSwap on the StrategyMainnet.sol

dharkartz

Summary

The _swapUnderlyingToAsset function includes a minOut check to ensure that the expected output of ALETH is greater than the input amount of WETH. However, the current implementation does not enforce the 1% premium specified in the comment. As a result, the function only validates that the minOut is greater than the input amount.

Vulnerability Details

The current implementation includes the following check:

require(_minOut > _amount, "minOut too low");

This ensures _minOut is greater than _amount, but it does not limit _minOut to the desired upper bound, i.e., ((_amount \* 101) / 100). For example:

  • If _amount = 1, the valid range for _minOut should be (1, 1.01).

  • However, the function allows _minOut values higher than 1.01, which might indicate a logic or configuration issue.

This discrepancy can lead to trades being executed without guaranteeing the desired exchange rate, possibly resulting in financial loss or inefficiency.

Impact

  • Financial Loss: The protocol may accept swaps at a higher premium than intended.

  • Misalignment with Business Logic: The intended 1% premium is not enforced, resulting in behavior that deviates from expected standards.

Tools Used

Manual Code Review

Recommendations

  • Enforce Premium Validation: Update the function to enforce that minOut meets the calculated premium:

uint256 maxPremium = (_amount * 101) / 100;
require (_minOut > _amount && _minOut <= maxPremium,"minOut must be within valid range")
Updates

Appeal created

inallhonesty Lead Judge 10 months ago
Submission Judgement Published
Invalidated
Reason: Non-acceptable severity

Support

FAQs

Can't find an answer? Chat with us on Discord, Twitter or Linkedin.