Submission Details
Severity:
Wrong Logic in `claimThrone` Function, it blocks any user from claiming the throne **Description:** ```solidity function claimThrone() external payable gameNotEnded nonReentrant { require(msg.value >= claimFee, "Game: Insuffic
Description:
function claimThrone() external payable gameNotEnded nonReentrant {
require(msg.value >= claimFee, "Game: Insufficient ETH sent to claim the throne.");
@> require(msg.sender == currentKing, "Game: You are already the king. No need to re-claim.");
...
}
This logic incorrectly checks if the sender is the current king, which prevents any non-currentKing from claiming the throne.
The check should be to ensure that the sender is not the current king, allowing anyone else to claim it.
Impact: Since initial value of currentKing is address(0), this logic blocks any user from claiming the throne, effectively making the game unplayable.
Proof of Concept:
add the following test to Game.t.sol and run it
function testClaimThrone_Blocked() public {
uint256 claimFee = game.claimFee();
assertEq(game.currentKing(), address(0));
vm.startPrank(player1);
vm.expectRevert("Game: You are already the king. No need to re-claim.");
game.claimThrone{value: claimFee}();
vm.stopPrank();
}
Recommended Mitigation:
change the logic to any non-currentKing can claim the throne
function claimThrone() external payable gameNotEnded nonReentrant {
require(msg.value >= claimFee, "Game: Insufficient ETH sent to claim the throne.");
- require(msg.sender == currentKing, "Game: You are already the king. No need to re-claim.");
+ require(msg.sender != currentKing, "Game: You are already the king. No need to re-claim.");
...
}
Updates
Appeal created
inallhonesty about 2 months ago
Submission Judgement Published Assigned finding tags:
Game::claimThrone `msg.sender == currentKing` check is busted
Rewards breakdown
nSLOC
181This contest has a flat reward structure with the following payouts:
100 EXP
20 EXP
2 EXP
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