auf http://download.cnet.com/8301-2007_4-10010614-12.html ist im Absatz "Downloads that use the CNET Installer" zu lesen:

This software is downloaded as an alternative to the full application installer...

Allerdings sowohl

we will also present offers for software that we think may be of interest to our users at the same time that we deliver your download.

, als auch

...does not leave behind any additional components.

Angeblich kann man das auch ablehnen:

These offers are clearly disclosed during the installation process, and users are given the opportunity to accept or decline them.

aber beim Öffnen mit wine bin ich sofort im nmap-5.51-setup.exe, ohne irgend etwas gefragt zu werden, was Toolbars, Hijacking o.ä. angeht.