Avci - the `batchTelcoin` will always fail due to wrong check in require.

[sherlock-admin2]

Avci

medium

the batchTelcoin will always fail due to wrong check in require.

Summary

the batchTelcoin will always fail due to wrong check in require.

Vulnerability Detail

in contract Telcoindistributor.sol the function batchTelcoin will always fail because it contains a require which revert if the initial balance of this contract and balance aren't equal after the token transfer!

Impact

the whole function of batchTelcoin are not going to work at all and will not batchtransfer token! cause this check is blocking it.

Code Snippet

look at this function first it stores the balance of the contract in the initialbalance and then it does the transfer process as it suppose to be but suddenly it checks the initialbalance is == to balance which is wrong cause balance of contract going to be changed anyway but it reverts and blocks the transfer process.

    function batchTelcoin(
        uint256 totalWithdrawl,
        address[] memory destinations,
        uint256[] memory amounts
    ) internal {
        // stores inital balance
        uint256 initialBalance = TELCOIN.balanceOf(address(this));
        //transfers amounts
        TELCOIN.safeTransferFrom(owner(), address(this), totalWithdrawl);
        for (uint i = 0; i < destinations.length; i++) {
            TELCOIN.safeTransfer(destinations[i], amounts[i]);
        }
        //initial balance is used instead of zero
        //if 0 is used instead stray Telcoin could DNS operations
        require(
            TELCOIN.balanceOf(address(this)) == initialBalance,
            "TelcoinDistributor: must not have leftovers"
        );
    }

https://github.com/sherlock-audit/2024-01-telcoin/blob/0954297f4fefac82d45a79c73f3a4b8eb25f10e9/telcoin-audit/contracts/protocol/core/TelcoinDistributor.sol#L185

Tool used

Manual Review

Recommendation

• the require at the end of the batchTelcoin should be removed or fixed but not checking equality after transfer.

[nevillehuang]

Invalid, DoS is not possible given logic execute within the same transaction, where in tokens are first transferred from owner to Distributor address, and then to destinations