Zombies: Is Your Computer Being Used By A Spammer to Send Out Spam Emails Without You Knowing?

Zombie Spam Machines
Is Your Computer Infected and Sending Out Spam Without You Knowing?

There has been quite a bit of news about viruses, phishing attempts and spam, but little warning about zombies.  Not the kind of zombie on late night tv movies, but a type of computer virus that infects your pc and causes it to send out spam emails, by the millions, for a spammer.  The spammer controls and uses your pc without you knowing it.

How do zombies work?

Spammers may be using your computer to send unsolicited - and possibly offensive - email
offers for products and services. Spammers are using home computers to send bulk emails by the
millions. Indeed, computer security experts estimate that as much as 30 percent of all spam is relayed by infected computers actually located in home offices and living rooms, but controlled from spammers from afar.

According to the Federal Trade Commission (FTC), the nation's consumer protection agency,
spammers can get into your computer in several ways, depending on what kind of Internet connection you have. All computers connected to the Internet are potential targets, but those with broadband (dsl, cable modem) connections are especially attractive to spammers because they are "always on."

Spammers scan the Internet, searching for points of entry and then install hidden software that allows remote access to your data and programs. That, in turn, allows the spammer to send relay their spam and send the spam messages out from your computer.

How does your computer become infected with a zombie?

Remote access software also can be installed by a virus: A spammer sends email with a virus in the
attachment. If you open the infected attachment, a virus is released that installs the hidden software.The person who sent the virus now can access the data and programs on your computer, or take over many computers and use them to send spam.

How would you now if your pc is a zombie?

It can be very difficult to tell if a spammer has installed hidden software on your computer, but
there are some warning signs. For example,

  • you may receive emails accusing you of sending spam;
  • you may find email messages in your "outbox" that you didn't send; or
  • your computer is using more power than it has in the past to run the programs you use. (typically, the computer becomes slower to respond)

If your computer has been taken over by a spammer, you could face serious problems. Your
Internet Service Provider (ISP) would see the huge number of emails coming out from your account and may prevent you from sending any email at all until the virus is treated, and treatment could be a complicated, time-consuming process.

How do I prevent my computer becoming a zombie?

  • Anti-virus software: Use anti-virus software and keep it up to date. You can download anti-virus software from the
    Web sites of software companies or buy it in retail stores. Look for anti-virus software that recognizes current viruses, as well as older ones; that can effectively reverse the damage; and that updates automatically. CFR recommends McAfee, Norton (Symantec), Zone Alarm and Kapersky.  And for a free option, AGV is pretty good.
  • Don't open unknown emails: Be cautious about opening any attachment or downloading any files from emails you receive.
    Don't open an email attachment - even if it looks like it's from a friend or coworker - unless you
    are expecting it or know what it contains. If you send an email with an attached file, include a text
    message explaining what it is.
  • Use a firewall to protect your computer from hacking attacks while it is connected to the Internet. A firewall is software or hardware designed to block hackers from accessing your computer. A properly configured firewall makes it tougher for hackers to locate your computer and get into your
    programs and files. A firewall is different from anti-virus protection: Anti-virus software scans
    incoming communications and files for troublesome files; a firewall helps make you invisible on the
    Internet and blocks all communications from unauthorized sources. It's especially important to run a firewall if you have a broadband connection.
    • Software firewalls: MS Wndows (XP and Vista) has a software firewall built-in, but you must turn it on. Because it may be shipped in the "off" mode, check your online "Help" feature for specifics on turning it on and setting it up properly. If your operating system doesn't include a firewall, you can install separate firewall software that runs in the background while you use your computer and surf the Internet. Several free firewall software programs are available on the Internet. (You can find one by typing "free firewall" into your favorite search engine.)
    • Hardware firewalls are considered to be stronger.  Most routers (like Dlink, Linksys, Netgear) have hardware firewalls built-in. A hardware firewall is an external device that includes firewall software. Like anti-virus software, a firewall needs to be updated regularly to stay effective.
  • Check your "sent items" file or "outgoing" mailbox to see if there are messages that you did not intend to send. Many spammers have learned to delete or hide their unauthorized access, so even if there are no illegitimate messages in your outbox, you can't be sure that your computer hasn't been used to send spam.

What do I do if my pc is a zombie?

If your computer is infected, take action immediately. If your computer has been hacked or
infected by a virus, you should:

  • Disconnect from the Internet right away. (Unplug the cable connecting you to the DSL router, cable modem - the box typically made by Dlink, LinkSys, Netgear or Airlink) Usually, the cable is blue or yellow.
  • Next scan your entire computer with fully updated anti-virus software.
  • Report any unauthorized accesses that the anti-virus software finds to your ISP. Also, if you suspect that any of your passwords have been compromised, call that site's company immediately and change your password.

How can I learn more about Zombies?

Learn more about securing your computer at from the FTC's security page. The FTC works for the consumer to prevent fraudulent, deceptive, and unfair business practices in the marketplace and to provide information to help consumers spot, stop, and avoid them.

To file a complaint see this page or call toll-free, 1-877-FTC-HELP (1-877-382-4357); TTY: 1-866-653-4261. The FTC enters Internet, telemarketing, identity theft, and other fraud-related complaints into Consumer Sentinel, a secure, online database available to hundreds of civil and criminal law enforcement agencies in the U.S. and abroad.

For More Information About Spyware and Adware, See:

And please let us know about any suspicious calls or emails you receive.  We look for patterns so that we can alert the authorities and victims to new scams, before it is too late!




For a comprehensive list of national and international agencies to report scams, see this page.