Submitted by leastwood, also found by JMukesh
The current ownership transfer process involves the current owner calling NoteERC20.transferOwnership(). This function checks that the new owner is not the zero address and proceeds to write the new owners address into the owners state variable. If the nominated EOA account is not a valid account, it is entirely possible the owner may accidentally transfer ownership to an uncontrolled account, breaking all functions with the onlyOwner() modifier. See NoteERC20.sol L123-L127.
Recommend considering implementing a two step process where the owner nominates an account and the nominated account needs to call an acceptOwnership() function for the transfer of ownership to fully succeed. This ensures the nominated EOA account is a valid and active account.
jeffywu (Notional) confirmed
