43.2.7. Securing Sendmail

43.2.7. Securing Sendmail

Sendmail is a Mail Transport Agent (MTA) that uses the Simple Mail Transport Protocol (SMTP) to deliver electronic messages between other MTAs and to email clients or delivery agents. Although many MTAs are capable of encrypting traffic between one another, most do not, so sending email over any public networks is considered an inherently insecure form of communication.

Refer to Chapter 24, Email for more information about how email works and an overview of common configuration settings. This section assumes a basic knowledge of how to generate a valid /etc/mail/sendmail.cf by editing the /etc/mail/sendmail.mc and using the m4 command.

It is recommended that anyone planning to implement a Sendmail server address the following issues.


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