`SablierV2Lockup::withdrawMaxAndTransfer` function transfers NFT by calling `ERC721::_transfer` function, could lead to potential NFT loss.
Vulnerability Details
The SablierV2Lockup::withdrawMaxAndTransfer function is used for withdrawing the maximum amount of tokens from the stream to the current recipient and then transfering the NFT to the new recipient, so that the new recipient can withdraw tokens from the stream. However, the way the NFT is transfered is by using the ERC721::_transfer function, which does not check whether the recipient is aware of the ERC721 protocol. This could lead to potential NFT loss.
Impact
If the recipient is a contract which is not aware of incoming NFTs, then the transferred NFT would be locked in the recipient forever.
Tools Used
Manual Review
Recommendations
Consider using ERC721::_safeTransfer, which checks if contract recipients are aware of the ERC721 standard to prevent tokens from being forever locked.
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Info/Gas/Invalid as per Docs
https://docs.codehawks.com/hawks-auditors/how-to-determine-a-finding-validity
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