Summary

Using string.concat for string concatenation is expensive in terms of gas and can lead to increased transaction costs.

Vulnerability Details

The string.concat function, used for concatenating strings, consumes a significant amount of gas. This is because string operations in Solidity are generally costly due to the nature of how strings are handled in the EVM. Each character in a string takes up a byte, and concatenating strings requires allocating memory and copying data, which leads to high gas costs.

Impact

• Increased transaction fees for users.

• Potential denial of service if the gas cost exceeds block gas limits in complex transactions.

• Reduced efficiency and higher operational costs for the contract.

Tools Used

Manual Inspection

Recommendations

Consider optimizing the logic to minimize the use of string concatenation.