That's an interesting question. You might post it on our dedicated download forum http://forums.cnet.com/download-site-feedback-forum/ also.
My view is that the software we offer there is explicitely uploaded to us (www.upload.com) with the request to make it available. I've never done so, but I assume there's an implicit or explicit agreement then between the maker and CNET that allows us to use the logo on the specific download page.
I've asked the forum administrator to have a look at your question also.
I'm a law student and I'm doing some research regarding the legality of download sites, like cnet.
Why is it ok for cnet to use logos from other companies, example Frostwire, and to provide downloads of Frostwire (for example)?
I have a few ideas, but just want to see what you think (that is part of my research as well, public opinion).
Thank you VERY much, I really look forward to seeing your thoughts/rationale.