Firefox not opening some websites

Hi guys,

I just installed OpenSUSE Leap 42.3 on Oracle VirtualBox 5.2.8.
First thing to do was to open Firefox and try google.com . I get “Secure Connection Failed” . Then I tried other websites yahoo.com (not working) , bing.com(working), facebook.com(not working). Tried also some local websites ending .bg and they all work just fine. Out of the VirtualBox I can open everything.

Did anyone faced something like that? Can this be fixed?

I’m new to Linux :slight_smile:

Thanks in advance.