Summary

This report presents the results of my audit of the Soulmate project's smart contracts. The audit revealed several areas for improvement and potential security concerns that should be addressed.

Vulnerability Details

Cache Array Length Outside of Loop (G002)

• Description: The length of the niceWords array is computed within a loop, which could be optimized by caching the length outside of the loop.

• File: Soulmate.sol

• Line: 119

Long Revert Strings (G007)

• Description: Long revert strings in the code suggest room for improvement in gas efficiency.

• File: Soulmate.sol

• Line: 21

Use Bitwise Shift Instead of Division/Multiplication (G008)

• Description: Arithmetic operations could be replaced with bitwise shift operations for better performance.

• Files: Airdrop.sol and Soulmate.sol

• Lines: 20, 140

Unsafe ERC20 Operations (L001)

• Description: Potentially unsafe ERC20 operations, such as transferFrom, should be reviewed for security risks.

• Files: Airdrop.sol and Staking.sol

• Relevant Lines: Multiple instances

Unspecified Compiler Version Pragma (L003)

• Description: The compiler version specified in the pragma statements is broad, which could lead to unintended consequences with future compiler versions.

• Files: Various

• Relevant Lines: First lines of each file

Impact

These issues could affect the overall efficiency and security of the smart contracts. Addressing them is crucial to ensure the contracts operate as intended and to protect users' assets.

Tools Used

The audit was conducted using c4udit, a tool designed to identify common issues in Ethereum smart contracts.

Recommendations

• Implement array and loop optimizations to minimize gas usage.

• Review and condense revert strings to lower transaction costs.

• Replace arithmetic operations with bitwise shift operations where applicable.

• Thoroughly review ERC20 operations to ensure security.

• Specify a more precise compiler version in pragma statements to prevent future compatibility issues.