First Flight #2: Puppy Raffle

Summary

players is stored in address arrays, A very large arrays might cause enterRaffle function to always be unable to complete, causing Denial of Service for this contract.
This is also not necessarily malicious, an organic growth in the players array could also cause this to happen.

Vulnerability Details

enterRaffle loop through the address array to check for duplicates (using double loop). For a sufficiently large array, it is possible that this function might never complete (since the gas requirement is so large it might exceed the block's gas limit for example, or it could just be sufficiently expensive to economically deter anyone to enter the raffle)

Impact

After certain entries, user won't be able to enter raffle anymore
Malicious attacker could also use many different addresses to enter the raffle, lengthening the arrays artificially hence breaking the contract. although the entranceFee provide economic deterrent against doing this.

Tools Used

Foundry

Recommendations

consider other mechanisms of storing raffle entries like using mapping instead of arrays.