Beatland Festival

AI First Flight #4
Beginner FriendlyFoundrySolidityNFT
EXP
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Submission Details
Severity: medium
Valid

configurePass resets passSupply allowing minting beyond maxSupply

Summary

configurePass resets passSupply[passId] to 0 on every call, allowing more passes to be minted than maxSupply.

Vulnerability Details

In FestivalPass.sol:65:

passSupply[passId] = 0; // Reset current supply

If 100 passes were sold and organizer calls configurePass(3, newPrice, 200), supply resets to 0. Another 200 can mint, totaling 300 while passMaxSupply shows 200. This is an implementation bug — the function updates price/maxSupply but the supply reset is an unintended side effect.

Impact

HIGH — Supply guarantees broken. "Limited edition" passes inflated by reconfiguration. Holders lose scarcity value.

Proof of Concept

function testSupplyReset() public {
vm.prank(organizer);
festivalPass.configurePass(3, 0.25 ether, 2);
vm.prank(user1);
festivalPass.buyPass{value: 0.25 ether}(3);
vm.prank(user2);
festivalPass.buyPass{value: 0.25 ether}(3);
// maxSupply reached (2/2), reconfigure resets supply
vm.prank(organizer);
festivalPass.configurePass(3, 0.25 ether, 2);
vm.deal(user1, 10 ether);
vm.prank(user1);
festivalPass.buyPass{value: 0.25 ether}(3);
assertEq(festivalPass.passSupply(3), 1); // Shows 1, but 3 exist
}

Recommended Fix

Remove passSupply[passId] = 0; or add:

require(passSupply[passId] == 0, "Cannot reconfigure after sales");
Updates

Lead Judging Commences

ai-first-flight-judge Lead Judge 2 days ago
Submission Judgement Published
Validated
Assigned finding tags:

[M-01] [H-1] Reseting the current pass supply to 0 in the FestivalPass::configurePass function allows users to bypass the max supply cap of a pass

# \[H-1] Reseting the current pass supply to `0` in the `FestivalPass::configurePass` function allows users to bypass the max supply cap of a pass ## Description: ```solidity function configurePass(uint256 passId, uint256 price, uint256 maxSupply) external onlyOrganizer { require(passId == GENERAL_PASS || passId == VIP_PASS || passId == BACKSTAGE_PASS, "Invalid pass ID"); require(price > 0, "Price must be greater than 0"); require(maxSupply > 0, "Max supply must be greater than 0"); passPrice[passId] = price; passMaxSupply[passId] = maxSupply; @> passSupply[passId] = 0; // Reset current supply } ``` If you reset `passSupply[passId]` to `0` in the `FestivalPass::configurePass` function after passes have been sold, the next buyer will be able to mint as if no passes have been sold. This allows the total minted passes to exceed `passMaxSupply`, which is a serious vulnerability (a supply cap bypass) ## Impact: * Supply caps become meaningless: The users can mint unlimited passes beyond the intended maximum supply * Pass scarcity and value are destroyed, affecting the economic model ## Proof of Concept: ```solidity function test_SupplyCapBypassVulnerability() public { // Step 1: Configure a pass with max supply of 2 vm.prank(organizer); festivalPass.configurePass(1, GENERAL_PRICE, 2); // Step 2: Buy 2 passes (reaching max supply) vm.prank(user1); festivalPass.buyPass{value: GENERAL_PRICE}(1); vm.prank(user2); festivalPass.buyPass{value: GENERAL_PRICE}(1); // Verify max supply reached assertEq(festivalPass.passSupply(1), 2); assertEq(festivalPass.passMaxSupply(1), 2); // Step 3: Try to buy another pass - should fail address user3 = makeAddr("user3"); vm.deal(user3, 10 ether); vm.prank(user3); vm.expectRevert("Max supply reached"); festivalPass.buyPass{value: GENERAL_PRICE}(1); // Step 4: VULNERABILITY - Organizer reconfigures the pass // This resets passSupply[1] to 0, bypassing the supply cap! vm.prank(organizer); festivalPass.configurePass(1, GENERAL_PRICE, 2); // Step 5: Now we can buy more passes even though max supply was already reached vm.prank(user3); festivalPass.buyPass{value: GENERAL_PRICE}(1); // Step 6: We can even buy more passes beyond the original max supply vm.deal(user4, 10 ether); vm.prank(user4); festivalPass.buyPass{value: GENERAL_PRICE}(1); // Step 7: Verify the vulnerability - total supply exceeds max supply assertEq(festivalPass.passSupply(1), 2); // Current supply counter assertEq(festivalPass.passMaxSupply(1), 2); // Max supply limit // But we actually have 4 passes minted in total! assertEq(festivalPass.balanceOf(user1, 1), 1); assertEq(festivalPass.balanceOf(user2, 1), 1); assertEq(festivalPass.balanceOf(user3, 1), 1); assertEq(festivalPass.balanceOf(user4, 1), 1); // Total minted: 4 passes, but max supply is only 2! uint256 totalMinted = festivalPass.balanceOf(user1, 1) + festivalPass.balanceOf(user2, 1) + festivalPass.balanceOf(user3, 1) + festivalPass.balanceOf(user4, 1); assertGt(totalMinted, festivalPass.passMaxSupply(1), "VULNERABILITY: Total minted exceeds max supply!"); } ``` ## Recommended Mitigation: The `passSupply` reset should be removed ```diff function configurePass(uint256 passId, uint256 price, uint256 maxSupply) external onlyOrganizer { require(passId == GENERAL_PASS || passId == VIP_PASS || passId == BACKSTAGE_PASS, "Invalid pass ID"); require(price > 0, "Price must be greater than 0"); require(maxSupply > 0, "Max supply must be greater than 0"); passPrice[passId] = price; passMaxSupply[passId] = maxSupply; - passSupply[passId] = 0; } ```

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