Xupiter and other Parasites
Ok. I'm a bit miffed. Yesterday I got hit twice by Xupiter. If you haven't experienced this, you really don't want to. Basically, Xupiter is a search engine with some not so nice advertising practises. They install their own toolbar, update engine (thus making registry changes) and puts their site as your homepage, WITHOUT ASKING YOU. This kind of activity may be the way that the so-called "All Windows Affected Vulnerability" occurred. It plays on legimate activity.
That said I do not believe there is a legal right for Xupiter to install on machines without the owner/user's permission as this is a basic "break and enter" concept.
For those that get infected or want more info, there isn't much but I did find the following site on how to remove these problems.