Legal or not..? Unasked for software riding in on downloads.

The solution is simple, NEVER, EVER use third party sites for downloading programs. ALWAYS go to the OFFICIAL developer site and get a direct download there, that's warranted to at least haven't being tampered by someone else.
Of course, nothing prevents that those can still be infected by something else by the original developer too, but the vast majority aren't, and you are sure you're getting the latest version too. Really, if you're still using CNET or any such sites to get software available in their official homepage, you're asking for problems.

Malwarebytes in particular always provided their official download here: Malwarebytes : Thank You!

I would doubt if some software developer was unable to provide their own official downloads, relying only on third party crapware sites for distribution. It's often preferable to look for more serious alternatives in those cases.

It wasn't always a direct download from them. Your link is a direct download, I believe a link to a download is the preferred method here.

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