You should just remove the script or make clear that it will potentially annihilate the victims host up to the point of rendering it unbootable. "apt-get upgra

You should just remove the script or make clear that it will potentially annihilate the victims host up to the point of rendering it unbootable. "apt-get upgrade" is not a safe operation. It will install new kernels and boot-loaders and it may get terribly confused in the face of pinned packages or mixed repositories. "--assume-yes" is a really bad idea and running "apt-get upgrade" is none of your installers business in first place.