Cross Bow.

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Rather Deep.

Compund Finance storage collision Compound Finance is one of the largest Fianace yet . It lets users to deposit their ETH or the acceptable ERC-20 into the contract . Based on the deposited ETH user recieve corresponding amount of cToken. User can redeem their token back by burning the cToken. It also specially integrates the TUSD , this has rather a special functionality , the compound mostly relies on TUSD if user deposits the TUSD the compound Fi mints the cTUSD. Vulnerability Details So t...

Smart contracts often revert due to some errors in the EVM , the funds will be reverted and returned to the orignal msg.sender ,and remaining gas is also returned in some cases.

We got an intresting attack vector using these cases. Because

of when cross chain transactions occur it losses its atomicity if a call reverts on destination chain the sender chain wouldn’t know . Causing insolvency between chains. Ofcourse There are methods the reslove this .

You send tokens from Chain A to Chain B via Axelar
Axelar burns your tokens on Chain A immediately
Then tries to execute your contract call on Chain B
If Chain B fails → your tokens are gone forever

To Resolve this edge case we need emit a message know that in the destination chain that the transaction(tx) was reverted and following-ly , If the emitted message is read by the sender chain [chain A] it should revert the transaction.The Destination chain and the sender chain both need to monitor the emits.