What stops someone from MITM-attacking the request to the certificate authority to verify the certificate? Does the browser come pre-loaded with the public keys of the trusted certificate authorities (thereby providing authentication)?
Whenever I think about MITM attacks, I think that any defence requires a "safe" connection to be established for authentication, and that the initial establishment of any "safe" connection always seems to be subject to a MITM attack itself. So for example, if the public keys of the trusted certificate authorities above are indeed distributed with the browser, the distribution of the browser would be subject to MITM attacks. As I understand it, even if you physically handed someone a public key / certificate / anything on a piece of paper, you had better know them from elsewhere otherwise they could be a MITM.
Do I understand this correctly?
Thanks!