Sunday, January 23, 2011


Email Security Problems | Where It Starts

You may be wondering when does the security problems are introduced. The answer is that they are usually introduced by the MUA. It’s a tool / software that we use to compose mails.

When you create an e-mail message, the client software you use is called a Mail User Agent (MUA). When you send your message, you send it to a server called a Mail Transfer Agent (MTA).  An MTA is responsible for transferring your message to a single server or collection of additional MTA servers, where it is finally delivered. The server that holds the message so that it can be read is called a Mail Delivery Agent (MDA). Your friend can then use his or her MUA to communicate with the MDA to download your message. The message is then delivered to an MDA, where the receiving MUA downloads the message.

There are several reasons for this:

  • MUA software, such as Netscape Messenger, is designed for convenience rather than security.
  • The software is often upgraded, quickly produced, and is not meant to conceal information.
  • The applications are often used by naïve end-users who use default settings.
  • When the MUA logs in to the MDA POP3 or IMAP server, authentication information is often sent in clear text format. In other words, the password information is not encrypted, and can be sniffed off the Internet by malicious users.
  • Users will often double-click an e-mail attachment without knowing its origin. If this attachment contains malicious code, a chain reaction will occur, which usually involves having the MUA send unsolicited messages to other MUAs. The result is an everincreasing stream of traffic that can bog down the sending servers (the MTAs), as well as the MDA.

It is possible for problems to be introduced at the MTA level, as well as at the MDA level. But the major concern is just from the user side.


About bench3 -

Haja Peer Mohamed H, Software Engineer by profession, Author, Founder and CEO of "bench3" you can connect with me on Twitter , Facebook and also onGoogle+

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