QSearch Mac Browser Hijacker
QSearch is a browser hijacker and a potentially unwanted application that only targets Mac systems at the moment. Browser hijackers are a subcategory of potentially unwanted applications or PUAs. PUAs in general occupy a gray, hazy area between legitimate software and full-blown malware.
While a PUA is never as dangerous as a remote access trojan, a virus, or ransomware, it will usually hamper and diminish the user's experience in some way or collect data about their PC use or browsing habits and often resell this information to third parties without the user's explicit consent.
In the case of QSearch, it will usually change your favorite browser's home page and default search engine. The fact that this happens without the user's permission and knowledge is what classifies QSearch and apps with similar functionality as PUAs.
If you see a lot of your regular searches are being redirected through qsearch dot cc or analytics dot qsearch dot cc, chances are you have the same browser hijacker on your Mac. The most likely origin of the browser hijacker is a download website that was not trustworthy. Similar free download websites would sometimes host app bundle installers. In those bundles, you would commonly find one legitimate application with one or more PUAs riding along, without disclosing their presence adequately or at all.
The best way to steer clear of this sort of thing is to always use well-curated, reliable websites for all your apps, such as the Apple App Store. Another option is to download all your applications directly from the publishers' websites and steer clear of free download websites entirely, just to be on the safe side.