Let's suppose I go to https://www.example.com using Tor. I check that the URL is correct, and the lock icon is present. But the exit node could be run by an adversary who uses a MITM attack and intercepts all the traffic. I download the SSL cert, then download the SSL cert from the same webpage, not through Tor, and do a binary comparison. Or else I compare the cert's serial number and SHA-256 fingerprint. If they match, can I be guaranteed the website viewed through Tor is legit? Or can those details be faked?
I am assuming the genuine cert for example.com has not been compromised.
I looked at plugins like convergence, but my questions relates specifically to checking the cert manually.