2.6. Surviving Malicious Code

Malicious code refers to a broad category of software threats to your network and systems, including viruses, Trojan horses, bombs, and worms. Your users depend on you to help keep them safe from harm and to repulse these attacks. When successful, these attacks can be devastating to systems, and they can spread through an entire network. One such incident involved the Melissa virus that effectively brought the entire Internet down for a few days in March 1999. This virus spread to millions of Outlook and Outlook Express users worldwide. Variants of this virus are still propagating through the Internet.

The following sections will briefly introduce you to the types of malicious code you'll encounter. I'll also explain ...

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