Can it be easily changed?
Should I look for this option here and what can I change the plaintext parameter to?
exim4.conf.template
begin authenticators
smtp_relay_login:
driver = plaintext
public_name = LOGIN
hide client_send = : SMTP_RELAY_USER : SMTP_RELAY_PASS
Information from the scanner:
Description
The remote host is running an SMTP server that advertises that it allows cleartext logins over unencrypted connections. An attacker may be able to uncover user names and passwords by sniffing traffic to the server if a less secure authentication mechanism (i.e. LOGIN or PLAIN) is used.
See Also
Solution
Configure the service to support less secure authentication mechanisms only over an encrypted channel.
Plugin Output
tcp/587/smtp
The SMTP server advertises the following SASL methods over an
unencrypted channel on port 587 :
All supported methods : LOGIN, PLAIN
Cleartext methods : LOGIN, PLAIN