Tadle
Tadle
DeFiFoundry
27,750 USDC
View results
Previous Next
Submission Details
Severity: high
Valid

An incorrect parameter is being passed to the `CapitalPool::approve` in `TokenManager::_transfer`

amaron

Summary

the _transfer function calls approve function with the TokenManager address as a parameter:

ICapitalPool(_capitalPoolAddr).approve(address(this));

however, the CapitalPool::approve takes token address as an input, to call approve on.

​
/**
* @dev Approve token for token manager
* @notice only can be called by token manager
@> * @param tokenAddr address of token
*/
function approve(address tokenAddr) external {
address tokenManager = tadleFactory.relatedContracts(
RelatedContractLibraries.TOKEN_MANAGER
);
@> (bool success, ) = tokenAddr.call(
abi.encodeWithSelector(
APPROVE_SELECTOR,
tokenManager,
type(uint256).max
)
);
​
if (!success) {
revert ApproveFailed();
}
}

Vulnerability Details

This will cause unexpected errors and will render the protocol unusable, as all tokens that will require the approve function will revert when trying to transfer the tokens due to lack of allowance (approval hasn't really happened).

Impact

all transfers that require approvals will revert due to lack of allowance.

Tools Used

manual review

Recommendations

call CapitalPool::approve with the token address.

Updates

Lead Judging Commences

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

finding-TokenManager-approve-wrong-address-input

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. The argument up in the air is since the approval function `approve` was made permisionless, the `if` block within the internal `_transfer()` function will never be invoked if somebody beforehand calls approval for the TokenManager for the required token, so 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.

Support

FAQs

Can't find an answer? Chat with us on Discord, Twitter or Linkedin.