12.4. Mail Server Security

There are two types of mail server security that need to be considered: the message transfer agent (MTA) and the user mailboxes. Most security resources are focused on the MTA, because that is the program responsible for routing mail to and from network users. It has also, traditionally, been one of the weakest security points on the network. Weak MTA security cannot only lead to attacks on a network, it can also result in mail from an organization being blacklisted. An organization that winds up on an MTA blacklist will be unable to send mail to sites that subscribe to the blacklist.

Before reading any further, conduct an experiment to gauge how secure your organization’s MTA is. Visit the following website in your ...

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