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Submission Details
Severity: low
Invalid

Duplicate MultiSig Wallets Created Permanently

0x0107

Summary

The matchRewards() function creates a new MultiSigWallet contract every time a match occurs. This permanently deploys multiple duplicate wallets on-chain, leading to high gas costs, redundant storage, and potential loss of funds.

Vulnerability Details

matchRewards() in LikeRegistry.sol

function matchRewards(address from, address to) internal {
MultiSigWallet multiSigWallet = new MultiSigWallet(from, to); // ❌ Deploys new wallet every time!
​
(bool success, ) = payable(address(multiSigWallet)).call{value: rewards}("");
require(success, "Transfer failed");
}
​

Problem:

  • Every match deploys a new MultiSigWallet contract on-chain.

  • Users who match multiple times will generate multiple redundant wallets.

  • Old wallets remain permanently deployed, wasting gas & blockchain storage.

  • Funds can get stuck in unused wallets, as users may not track all deployed wallets.

PoC

1.Alice and Bob match the first time.

  • A new MultiSigWallet is deployed.

  • MultiSigWallet #1 is created.

2.Alice and Bob match again later.

  • Another MultiSigWallet is deployed.

  • MultiSigWallet #2 is created.

3.Both wallets exist permanently, increasing gas costs and on-chain clutter.

Unexpected Result: Alice and Bob now have two separate wallets for the same match, making it hard to track funds!

Impact

  • Permanent blockchain clutter: Every match deploys a new contract forever.

  • High gas fees: Unnecessary deployments waste user funds.

  • Lost funds risk: Users may not track multiple wallets, losing access to their funds.

Tools Used

Manual Review

Recommendations

Use a Mapping to Store Existing Wallets.

Modify matchRewards() to check if a wallet already exists before creating a new one.

// Store wallets
mapping(address => mapping(address => address)) public multiSigWallets;
​
​
function matchRewards(address from, address to) internal {
// Check if a wallet already exists
if (multiSigWallets[from][to] == address(0)) {
MultiSigWallet multiSigWallet = new MultiSigWallet(from, to);
multiSigWallets[from][to] = address(multiSigWallet); // Store wallet address
}
​
uint256 matchUserOne = userBalances[from];
uint256 matchUserTwo = userBalances[to];
​
userBalances[from] = 0;
userBalances[to] = 0;
​
uint256 totalRewards = matchUserOne + matchUserTwo;
uint256 matchingFees = (totalRewards * FIXEDFEE) / 100;
uint256 rewards = totalRewards - matchingFees;
totalFees += matchingFees;
​
address wallet = multiSigWallets[from][to]; // Use existing wallet
​
(bool success, ) = payable(wallet).call{value: rewards}("");
require(success, "Transfer failed");
}
​
Updates

Appeal created

n0kto Lead Judge 3 months ago
Submission Judgement Published
Invalidated
Reason: Design choice
Assigned finding tags:

Informational or Gas

Please read the CodeHawks documentation to know which submissions are valid. If you disagree, provide a coded PoC and explain the real likelyhood and the detailed impact on the mainnet without any supposition (if, it could, etc) to prove your point.

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