RustFund

Summary

The fund.amount_raised += amount operation does not use a safe arithmetic method like checked_add. In extreme edge cases, this might allow an overflow scenario.

Vulnerability Details

• Rust’s default for integer overflow in a non–release mode is to panic, but in some compilation settings (and especially in older Solana program contexts), it can wrap around silently.

• If fund.amount_raised were to approach u64::MAX, the next addition could wrap to a small number.

Impact

• Corrupted Logic: A wrap-around might cause the contract to incorrectly think goal is not met (or is re-met, etc.).

• Edge Attack Vector: Though highly unlikely in normal usage, it remains a theoretical exploit for extremely large sums.

Tools Used

• Analysis of arithmetic operations in the contribute function.

• Comparison with the best-practices of using secure mathematics in on-chain Rust code.

Recommendations

• Use checked_add when updating fund.accumt_raised and handle the overflow error (returning, for example, ErrorCode::CalculationOverflow).

• Add unit tests that check the behavior at the maximum possible values.