This will tip the server off as it won't receive the expected cyphertext. By doing a mitm interception with a newly injected public key and re-encrypting with

This will tip the server off as it won't receive the expected cyphertext. By doing a mitm interception with a newly injected public key and re-encrypting with the real key before sending to server, you can let the client-server carry on a conversation as usual, while you intercept the entire conversation. [Client] ---(fakekey)---- MITM ----(realkey)---- [Server]