If Chromium has installed by itself, chances are you’ve downloaded a potentially unwanted program with a malicious version of Chromium attached to it. If this is the case, it’s likely your computer has been infected with the Chromium virus and other, more dangerous types of malware.
You should follow our steps to safely uninstall Chromium and run a full disk scan on your computer using a comprehensive antivirus scanner (Norton is the best Windows antivirus, whereas Intego is the best antivirus for Mac).