Fractional v2 contest - peritoflores's results

Lines of code

https://github.com/code-423n4/2022-07-fractional/blob/8f2697ae727c60c93ea47276f8fa128369abfe51/src/modules/Migration.sol#L172 https://github.com/code-423n4/2022-07-fractional/blob/8f2697ae727c60c93ea47276f8fa128369abfe51/src/modules/Migration.sol#L325

Vulnerability details

Impact

Transaction can revert

Proof of Concept

The original transfer used to send ETH uses a fixed stipend of 2300 gas. This was used to prevent reentrancy. However, this limit your protocol to interact with others contracts that need more than that to proceess the transaction A good article about that https://consensys.net/diligence/blog/2019/09/stop-using-soliditys-transfer-now/

Recommended Mitigation Steps

Use call instead.

(bool success, ) = msg.sender.call{ethAmount}("");
require(success, "Transfer failed.");

Lines of code

https://github.com/code-423n4/2022-07-fractional/blob/8f2697ae727c60c93ea47276f8fa128369abfe51/src/modules/protoforms/BaseVault.sol#L65 https://github.com/code-423n4/2022-07-fractional/blob/8f2697ae727c60c93ea47276f8fa128369abfe51/src/references/TransferReference.sol#L22

Vulnerability details

Proof of Concept

The ERC20.transfer() and ERC20.transferFrom() functions return a boolean value indicating success. This parameter needs to be checked for success. Some tokens do not revert if the transfer failed but return false instead. Tokens that don’t actually perform the transfer and return false are still counted as a correct transfer.

Recommended Mitigation Steps

Use OZ safeTransfer