setFee Function Lacks Access Control, Allowing Unauthorized Modifications to Transaction Fees

[BugmakerCC]

Filepath

contracts/multiply/DummyExchange.sol

Affected Code

function setFee(uint8 f) public {
    fee = f;
  }

Description

The setFee function in the DummyExchange contract lacks proper access control, allowing anyone to call the function and modify the fee parameter. This introduces a critical vulnerability that could lead to financial losses, service disruption, and trust issues for the platform.

Impact

Any user can call the setFee function and change the transaction fee to arbitrary values, including extreme values such as fee = 10000 (effectively a 100% fee).