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Correct me if I’m wrong, but isn’t the CA only signing your public key to prove identity/authority? I don’t think the CA can magically MITM every cert they sign.
The impact is not serious enough to warrant a $1m entry fee, IMO. At best, someone could impersonate a site. They’d also have to get other things in line (e.g. DNS hijacking) to be at all successful anyway. And it’s not like most people are authenticating certs themselves. They just trust browsers to trust CAs that vouch for you and prevents those scary browser warnings.
It doesn’t improve encryption compared to a self-signed cert though.
If you are the CA, you can sign a new certificate yourself for google.com and the browser will accept it. It’s effectively allows MITM for any certificate. Worse, it’s not even limited to certificates under that CA. The browser has no way of knowing there’s 2 “valid” certs at once, and in fact that is allowed regardless (multiple servers with different instances of the SSL cert is a possibility).
Certificate pinning might save things, since that will force the same certificate as was previously used, but I’m not sure this is a common default.
Correct me if I’m wrong, but isn’t the CA only signing your public key to prove identity/authority? I don’t think the CA can magically MITM every cert they sign.
The impact is not serious enough to warrant a $1m entry fee, IMO. At best, someone could impersonate a site. They’d also have to get other things in line (e.g. DNS hijacking) to be at all successful anyway. And it’s not like most people are authenticating certs themselves. They just trust browsers to trust CAs that vouch for you and prevents those scary browser warnings.
It doesn’t improve encryption compared to a self-signed cert though.
If you are the CA, you can sign a new certificate yourself for google.com and the browser will accept it. It’s effectively allows MITM for any certificate. Worse, it’s not even limited to certificates under that CA. The browser has no way of knowing there’s 2 “valid” certs at once, and in fact that is allowed regardless (multiple servers with different instances of the SSL cert is a possibility).
Certificate pinning might save things, since that will force the same certificate as was previously used, but I’m not sure this is a common default.