I have found a bug and the developers to whom I reported this bug to want me to send them the VM with the bug. They want me to send them the password and the VM in its current state (a snapshot). I don't want to give them the password I currently have for the VM, instead I am going to change the password for the VM to something else, and I don't want them to be able to figure out what my old password was.
So if I change the sudo password and give them a snapshot of the machine, with access to the machine and the new password is there any way that they could determine the old password? The machine is an installation of Ubuntu GNOME 15.10 with GNOME 3.18 64-bit.
I'm basically just wanting to know if it is still stored somewhere or something, and whether I'd be safer just doing a fresh install with a password I don't mind giving away, or whether once the password is changed, the old one can't be recovered and thus it doesn't matter if I just send them a snapshot with a new password.