First Flight #2: Puppy Raffle

Summary

Missing overflow checks in function selectWinner()

Vulnerability Details

Contract theoretically could be initialized with extremely high value for 'raffleDuration' that could cause overflow which happens quietly in solidity ^0.7.6.

Impact

The selectWinner() check 'require(block.timestamp >= raffleStartTime + raffleDuration, "PuppyRaffle: Raffle not over")' could be compromised by an overflow.

I set Medium severity because the likelihood is not high.

Tools Used

Manual review

Recommendations

Check for overflow