I don't know if, in my case, ISTART is "malicious".
They claim that they distibute their (harmless) "Desktop
Search" module to freeware providers of browsers to help
them in their business. In return, ISTART "helps" the
browser, by recording your keystrokes, keeping logs of
these, and making copies at their own company website, as
well as the provider's. I guess it's only malicious,if
they use the gathered information in an illegal manner,
rather than for business market research, or make your PC
slow down,perhaps fail. But how would you know? Besides,
ISTART is very difficult to remove, they say, unless you
visit their site, and let THEM remove it for you. It's
all a matter of trust, I guess.