Hi Nazkal. It would be good if you could provide some more information about this. With thousands of forums and several servers it's a bit hard to "go looking" for it...
Where exactly did you get this warning? On what forum(s) or domain(s) did you come across it?
ForumUp does not link to starware, or any other addware sites. Much less is there spyware "in" ForumUp sites. This does not exclude that there is a problem, but if so, it must be "local", and not all over ForumUp.
If links in this case includes "ordinary" links, in posts, profiles, etc. then the link that triggered the warning is likely to be found in a spambot profile. And if so, it must also be clicked to cause any harm.
FoxLeonard