MultiSig Wallet Could Be Drained via Replay Attack
Summary
Transactions in MultiSigWallet are approved by both users.
If the same txId is replayed after execution, the contract does not prevent reuse, which can drain funds.
Impact
Loss of funds
Tools Used
Manual Review
Recommendations
mapping to track executed transactions
mapping(uint256 => bool) public executedTransactions;
require(!executedTransactions[_txId], "Transaction already executed");
executedTransactions[_txId] = true;
Appeal created
Suppositions
You have to point a real root-cause leading to a bug. "If, may, could, unexpected behavior, incoherent" are not describing a real concrete bug. Please read the CodeHawks documentation to know which submissions are valid. If you disagree, provide a coded PoC and explain the real likelihood and the detailed impact on the mainnet without any supposition (if, it could, etc) to prove your point.
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