First Flight #4: Boss Bridge

Summary

The setSigner function is a one way function that allows you to enable permission for a given signer but there is no way to revoke that permission in the event that the signer goes rogue or that a third party gets access to that signer's private keys.

Vulnerability Details

setSigner lets you give permission but there is no way to revoke it:

Impact

If a signer goes rogue or a malicious third party gets access to a signer's keys, it could lead to stolen funds or interfere with the expected operation of the bridge (e.g., if the signer refuses to sign withdrawals).

Tools Used

Manual review

Recommendations

You should add a function to revoke signer addresses. Here is the function I recommend: