E-Mail Security - Facts and Fiction

E-Mail viruses and worms are spreading rampantly--how can you protect yourself?

There is a secret that nobody told you about e-mail:  E-Mail is NOT by default a secure form of communication.  While text e-mails don't spread viruses, e-mail attachments can.  Often e-mail viruses try and trick you, advertising themselves as a cool screensaver, a security fix, or something else attractive.  This is called a "Trojan Horse."  E-mail attachments may contain code which can spread the virus along to everyone in your address book.  This is a major problem with the way internet e-mail works, and in order to keep your computer secure, you need to know the ground rules: 

Just because an e-mail says it’s from somebody you trust, doesn’t mean it really is.

E-Mail headers can be forged.  There is no way around it with the current protocols.  It’s sent over the internet in plain text that anybody with the proper tools can manipulate maliciously.  There are two reasons you shouldn’t trust the FROM line of an e-mail:  1) while you may trust the person, his computer may be infected by a virus that he doesn’t know about.  2)  The FROM line of an e-mail may be entirely forged and came from somebody else.  Remember, e-mail is NOT secure and there is no built-in way to authenticate who an e-mail came from.  This brings us to the second rule…

Never open an e-mail attachment you don’t trust

You should never open an e-mail attachment from someone you don’t trust.  But don’t forget the first rule:  because you can’t trust an e-mail came from someone you do trust, you shouldn’t open an e-mail attachment from those people either!  This is the hardest part—you can’t even trust e-mail attachments from your mother!

The exception to this rule is when you are expecting an e-mail with an attachment from somebody.  You need a way to know that the person you trust is the actual person sending you those attachments.  It may require a phone call, or maybe you should just send a reply to the person and make sure they really did send you that attachment.  Confirmation such as that will go a long way towards keeping your system virus-free.

These rules are inconvenient but they are a necessity to keep your computer secure, even if you have anti-virus software installed.

What else can I do?

Anti-virus software may help, and they augment the common sense rules listed above.  However, you must keep your anti-virus software updated.  The anti-virus software works by scanning files and attachments for known viruses.  If there is a new virus that the anti-virus software doesn’t understand, the anti-virus software can’t stop the virus.  New viruses pop up all the time, therefore, the only way to stop e-mail viruses from infecting your computer is to never open untrusted e-mail attachments.

Conclusion

 The simple thing to remember is:  never open any attachments you don't trust. 

Back to Security