Spam Zombie

by Christopher on December 8, 2011

Perhaps you’ve been staggering around, drooling, staring off into space, and pawing without coordination at miscellaneous objects within your reach. Perhaps you’re a zombie. Perhaps it’s Monday morning, Jim’s still lurking around the coffee pot, and the idea of discussing your weekend with Jim makes you twitch with sensations of oncoming spontaneous combustion, so you haven’t had your coffee yet. Perhaps I’m already getting way off-topic and thinking about the wrong sort of zombies.

Many people assume that spam’s primary purpose is to sucker you into buying supplements that will fail to make any of your various organs grow larger. But a significant chunk of the spam circulating out there in the email ether has one directive: hijack new email accounts to proliferate the spread of more spam. Computers taken over in this way become part of what’s known as a robot network, or botnet, and are often referred to as “zombies.”

Spammers commonly use spam messages to bring more random, under-protected email accounts into the ranks of their zombie armies. Many botnets are comprised of tens or hundreds of thousands of the millions of home and business computers that have been compromised, and they are the source of the overwhelming majority of all spam, as the Federal Trade Commission reported in a recent consumer alert.

Your home or office computers can be turned into botnet zombies without your ever knowing. There are a few indications that may arise, including a significant slow-down in the machine’s performance, mysterious emails stored in your sent-mail folder, or baffling complaints about the spam “you” have been sending lately. However, even if you find out that spammers have hijacked your email account, damage was likely already done.

The leading anti-spam email protection technologies today make use of a method known as IP address reputation filtering. Basically, they keep track of what email accounts at specific IP addresses are up to, identifying those that act legitimately and those that act according to spammer patterns. Reputations are thus established for IP addresses, and spam filters consider a sender’s trustworthiness when deciding whether an incoming message is spam. If your home or business computers become zombies, you’ll eventually develop a bad reputation and your emails will be bounced or sorted into spam folders. Consequences can range from slightly inconvenient to completely devastating for personal and professional email uses alike.

As a zombie, your computer may also give a spammer access to files stored within and email addresses in your contact lists. “You” may suddenly start sending your recovering gambling addict boyfriend emails promoting online casinos, or encouraging your grandmother to start purchasing her life-saving medications directly from some guy in a barn in Bolivia. Imagine the interesting interactions you’ll have when your work email account starts sending special offers to your boss and your client roster. You may also find that your host or ISP isn’t particularly happy with you, which can result in your website being shut down or your internet account cancelled.

Being a zombie is so often glorified, what with getting to eat brains and all. But when your computer is taken over by a spammer and hooked into a botnet, life as a zombie can be a lot less glorious. Usually, all it takes is one wrong click. Be on guard, educate your employees about spam threats and signs of malware infection, and invest in up-to-date anti-spam filtering.

Posted in: Spam

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