CodeHawks Escrow Contract - Competition Details

Summary

The Arbitor can blackmail both the seller and buyer since they are in complete control when a dispute is initiated.

Vulnerability Details

When a dispute is started the s_state of the contract is set to Dispute. At this point the arbiter is the only entity that can move the funds, this means they can blackmail both the seller and buyer and hold the funds hostage.

The buyer/seller should always be able to set a new arbiter if they both chose to do so, this makes it impossible for the arbiter to blackmail them.

This is an issue if the arbiter loses access to his address, is compromised or is a malicious actor.

Impact

The arbiter can blackmail the buyer/seller since they are the only entity that can move the finds when a dispute starts.

Tools Used

manual review

Recommendations

Add a function that allows the buyer/seller to change the arbiter. They both have to agree on the same arbiter for the address to be changed.