In a TLS13 server, sending data before receiving Finished message should not be allowed by default. While it may be acceptable in some applications like SMTP banner, it gives less security properties (replay), and alters server behavior in case of handshake error.
In a TLS13 server, sending data before receiving Finished message should not be allowed by default. While it may be acceptable in some applications like SMTP banner, it gives less security properties (replay), and alters server behavior in case of handshake error.