Privacy Intrusion !

Why is BitDefender changing my SSL certificates and acting as a proxy to parse my secure traffic?

That's the only way it can scan SSL connections with doing nastier low-level browser hacks. If you don't want it to scan SSL traffic, uncheck the setting and it won't do it anymore.

Now, this is a perfectly normal thing to do... if they hadn't done such a shoddy job of it. Their MITM proxy reintroduces the Poodle and Freak vulnerabilities and doesn't seem to support things like certificate pinning and CRLsets that browsers like Chrome use to augment their SSL certificate validation.

BitDefender should really hire someone that understands SSL security and/or go back to doing what their good at, which is scanning for viruses. In the mean time, just uncheck scan SSL. You don't need it.