Take a look at https://github.com/code-423n4/2024-03-zksync/blob/4f0ba34f34a864c354c7e8c47643ed8f4a250e13/code/contracts/ethereum/contracts/bridge/L1ERC20Bridge.sol
Contract is obviously a bridge that allows for the depositing of ERC20 tokens to hyperchains, this means that the contract at some point would hold a lot of tokens and could be eligible for some airdrops, since its most likely going to be based on the snapshot of the token balance, now clearly this contract does not entail any sweeping functions and as such all airdrops sent to this contract are effectively stuck
Leak of value since there are no methods to get hold of the airdrops.
Introduce a sweeper functionality for these cases.
