It's a master public key if someone has access to this then they can only see all of your addresses on that zpub but they can't make any transaction.

If it was from multisig wallet then even you have them you won't be able to make transactions because it is just a master public key.
You can make an unsigned transaction from zpub but you won't be able to broadcast them so if you want it to become valid you will need to sign them.

What exactly do you want to achieve here?