Summary

The BuyerAgent contract and the SwanManager contract currently allow both the buyer agent fee and the platform fee to be set up to 100%, creating a scenario where the buyer can take all the seller asset price and the platform can take all the BuyerAgent Fees. This configuration leads to a significant overcharging risk:

Vulnerability Details

Buyer Agent Fee Cap: The buyer agent can set its fee to 100% of the asset price, which means the agent could take the entire value of the asset as a fee, potentially leaving the seller with no benefit from the transaction.

Platform Fee Cap: The platform fee can set its fee to 100% of the buyer agent fee, the platform can could take all the buyer agent Fee

Impact

This issue could lead to extreme cases where sellers lose 100% of the asset’s value in fees, and buyers can lose 100% of the fees gotten from sales. Such a setup creates a non-functional and non-viable system, as it is unlikely for users to accept transactions where they incur more in fees than the value of the asset itself.

Tools Used

Manual Review

Recommendations

Cap Fees at Reasonable Levels: Implement sensible maximum caps for both the buyer agent and platform fees.