Replying to @⁨Sibbo@sopuli.xyz⁩

What risk are you trying to mitigate, specifically?

If it’s the CA taking over your site, control over your CA specifically doesn’t really give any advantage to an attacker (they would have to hijack traffic and provide a new certificate - nobody will notice if the certificate is from a different CA).

Note that your CA cannot decrypt the exchanges between your server and its clients.

Replying to @⁨Mihies@programming.dev⁩

The CA cannot decypt: they don’t have the secret key which only the server has. When requesting a new certificate from the CA, the server generated a secret key (aka private key) and then generated a derived public key that goes into a Certificate Signing Request (CSR). The CSR is what the CA receives, not the secret key, and then the CA returns the certificate file to the server, which has been endorsed by the CA and thus trusted by the user base.

Phrased another way, a certificate is the instrument that confirms that a purported public key can in-fact be safely used, and that no MITM attack is happening (assuming you trust the CA that signed the cert). But once you’ve confirmed the public key, the rest of the cryptography is public key cryptography, meaning the secrecy of the secret key is the whole game.

Edited ⁨⁨Sep⁩ ⁨19⁩, ⁨2026⁩, ⁨17:05⁩⁩en