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Puppy Raffle
Submissions
AI First Flight
Puppy Raffle
AI First Flight #1
Beginner Friendly
Foundry
Solidity
NFT
EXP
AI First Flight
EXP
Oct 6th, 2026 → Oct 6th, 2026
View repo
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10 / 10
Submissions
Severity
Validity
Tags
Author
#1
Potential Front-Running Attack in `selectWinner` and `refund`: a losing player front-runs the draw with `refund` to escape, shrinking the pool
Medium
Invalid
hopeh
#2
Reentrancy in `PuppyRaffle::refund`: ETH is sent before the player slot is zeroed, allowing a contract to drain the entire balance
High
Valid
[H-02] Reentrancy Vulnerabi...
hopeh
#3
Randomness can be gamed: weak on-chain randomness in `selectWinner` (block.timestamp/block.difficulty/msg.sender) lets an attacker win
High
Valid
[H-03] Randomness can be gamed
hopeh
#4
`PuppyRaffle::refund` replaces an index with address(0) which can cause `selectWinner` to always revert (funds locked)
High
Valid
[H-04] `PuppyRaffle::refund...
hopeh
#5
Typecasting from uint256 to uint64 in `selectWinner` may lead to overflow and incorrect fee calculation (locks fees)
High
Valid
[H-05] Typecasting from uin...
hopeh
#6
Overflow/Underflow vulnerability for any version before 0.8.0: Solidity ^0.7.6 with no SafeMath (entranceFee * newPlayers.length)
High
Valid
[H-06] Overflow/Underflow v...
hopeh
#7
`enterRaffle` gas-extensive O(n^2) duplicate check leads to Denial of Service, making subsequent participants spend much more gas
Medium
Valid
[M-01] `PuppyRaffle: enterR...
hopeh
#8
Slightly increasing puppyraffle's contract balance will render `withdrawFees` function useless, permanently locking fees
Medium
Invalid
hopeh
#9
Impossible to win raffle if the winner is a smart contract without a fallback function (selectWinner reverts, funds locked)
Medium
Valid
[M-03] Impossible to win ra...
hopeh
#10
Potential Loss of Funds During Prize Pool Distribution: refunds leave phantom `players.length`, so `selectWinner` distributes more than collected
Medium
Invalid
hopeh
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