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Submission Details
Severity: high
Valid

Funds can be frozen in the withdraw function

dustinhuel2

Summary

Due to lack of approve in the withdraw function, user's funds can be frozen.

If a user creates an offer with the token not wrappedNativeToken in the TokenManager, he couldn't withdraw funds because there is no approve of that token in the contract.

Vulnerability Details

Suppose a user withdraw TaxIncome by USDC token. He calls follow statement.

tokenManager.withdraw(address(USDCToken), TokenBalanceType.TaxIncome);

But in the withdraw function, there is insufficient allowance when capital pool sends tax income to user(see _safe_transfer_from()). Because there is no approve of this USDC token for capital pool in the contract.

function withdraw(
address _tokenAddress,
TokenBalanceType _tokenBalanceType
) external whenNotPaused {
...
if (_tokenAddress == wrappedNativeToken) {
...
} else {
/**
* @dev token is ERC20 token
* @dev transfer from capital pool to msg sender
*/
_safe_transfer_from(
_tokenAddress,
capitalPoolAddr,
_msgSender(),
claimAbleAmount
);
}

Tools Used

Manual Review

Recommendations

Improve _updateTokenWhiteListed(), so capital pool approve white listed tokens.

function _updateTokenWhiteListed(
address _token,
bool _isWhiteListed
) internal {
tokenWhiteListed[_token] = _isWhiteListed;
address capitalPoolAddr = tadleFactory.relatedContracts(
RelatedContractLibraries.CAPITAL_POOL
);
if (capitalPoolAddr != address(0x0) && _isWhiteListed)
ICapitalPool(capitalPoolAddr).approve(address(_token));
​
emit UpdateTokenWhiteListed(_token, _isWhiteListed);
}
Updates

Lead Judging Commences

0xnevi Lead Judge about 1 year ago
Submission Judgement Published
Validated
Assigned finding tags:

finding-TokenManager-safeTransferFrom-withdraw-missing-approve

This issue's severity has similar reasonings to #252, whereby If we consider the correct permissioned implementation for the `approve()` function within `CapitalPool.sol`, this would be a critical severity issue, because the withdrawal of funds will be permanently blocked and must be rescued by the admin via the `Rescuable.sol` contract, given it will always revert [here](https://github.com/Cyfrin/2024-08-tadle/blob/04fd8634701697184a3f3a5558b41c109866e5f8/src/core/CapitalPool.sol#L36-L38) when attempting to call a non-existent function selector `approve` within the TokenManager contract. Similarly, the argument here is the approval function `approve` was made permisionless, so if somebody beforehand calls approval for the TokenManager for the required token, the transfer will infact not revert when a withdrawal is invoked. I will leave open for escalation discussions, but based on my first point, I believe high severity is appropriate. It also has a slightly different root cause and fix whereby an explicit approval needs to be provided before a call to `_safe_transfer_from()`, if not, the alternative `_transfer()` function should be used to provide an approval, assuming a fix was implemented for issue #252

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