If you think your home-based personal computer or computer network is invulnerable to "W32/SirCam@MM," "Code Red," and other computer nasties that recently have mounting digital attacks from cyberspace, think again: There is no such thing as perfect computer security.

Hackers, crackers, or computer intruders by any name could care less that your computer at home is used only for such mundane tasks as storing recipes or creating shopping lists.

Digital bad guys may want to gain control of your computer to launch attacks and wreak havoc on other computer systems.

Chances are, however, some personal, private and sensitive information dwells in the electronic crevices of your hard drive and you don't want strangers examining your personal data. More and more home-based computers also access the Internet via broadband technology that makes your computer or home network more vulnerable to break-ins.

With control of your computer, the silicon sneaks can hide their true identity and location as they watch your computer actions, destroy your data or launch attacks elsewhere.

Your are particularly vulnerable if you connect to the Internet, run programs of unknown origin and don't take adequate precautions, says the Pittsburgh, PA-based Computer Emergency Response Team Coordination Center, officially known as CERT/CC.

The center is the software security branch of the Software Engineering Institute (SEI), a U.S. Department of Defense research and development center created to make the acquisition, development, and sustainment of software-intensive systems predictably better, faster, and cheaper.

CERT/CC also devotes a section to home computer users.

"Even if you have a computer connected to the Internet only to play the latest games or to send e-mail to friends and family, your computer may be a target," the center says.

"Intruders are always discovering new vulnerabilities (informally called "holes") to exploit in computer software. Most of the incident reports of computer break-ins received at the CERT/CC could have been prevented if system administrators and users kept their computers up-to-date with patches and security fixes," the center says.

CERT/CC offers the following recommendations for home computer users.

• Consult with your employer's computer system support center if you work from home and connect to your employer's network. Your employer may have policies or procedures relating to the security of your home network.

• Use virus protection software and keep it up to date.

• Use a firewall. Hardware and software based firewalls can provide some degree of protection against attack. Don't install a firewall and neglect to follow other security measures.

• Do not open unknown e-mail attachments. E-mail attachments are often the deployment tool of choice among attackers. It is not enough to know the e-mail originated from an address you recognize. Many viruses spread because they arrive via familiar addresses. If you must open an attachment before you verify its source, be sure your virus definitions are up-to-date.

  Save the file to your hard disk and scan the file with anti-virus software before you open the file. Disconnecting your computer from a network before opening the file provides additional protection by preventing any let-loose malicious virus code from spreading.

• Don't run programs of unknown origin. Early viruses spread because of unsafe floppy disk sharing. Likewise, don't send programs of unknown origin to your friends or coworkers because you think them amusing.

• Disable hidden file name extensions. Windows operating systems contain an option to "Hide file extensions for known file types". The default is to enable this feature. Disable this feature so Windows displays the extensions. Stange file name extensions can alert you or your anti-virus software to a virus.

• Keep all applications, including your operating system, patched. Vendors typically release patches for their software when a vulnerability has been discovered.

• Turn off your computer or disconnect it from a network when not in use. Broadband access from home typically uses an Ethernet interface to network with the Internet. CERT/CC says an intruder cannot attack your computer if it is powered off or disconnected from the network.

• If possible, disable Java, JavaScript, and ActiveX. Turning off these options will limit the interaction you can have with some Web sites, but it will help keep you from being vulnerable to malicious scripts.

• Disable scripting features in e-mail programs. Because many e-mail programs use the same code as Web browsers to display HTML, vulnerabilities that affect ActiveX, Java, and JavaScript are often applicable to e-mail as well as Web pages. For information see: How To Turn Off Windows Scripting Host from ZDNet.com.

• No matter where you are, follow the three rules of computing -- backup, backup, backup. Regular backups of critical data made to removable media such as Iomega ZIP disks or recordable CD-ROM disks keeps your data secure and out of harms way in the event of an attack or non-virus related incident.

• Make a boot disk (from which you can start up your computer) in case your computer's operating system is damaged or compromised.

  The boot disk should also include virus protection and file recovery software to help you recover from a security breach or hard disk failure. Create the boot disk before you have a "security event."

For more articles by Broderick Perkins, please press here.

Published: August 10, 2001

Use of this article without permission is a violation of federal copyright laws.

A journalist for 35-years, Broderick Perkins parlayed an old-school daily newspaper career into a digital news service offering editorial content and consulting services. Perkins' San Jose, CA-based DeadlineNews Group includes the flagship news site, DeadlineNews.Com, offering real estate, personal finance and consumer journalism, and a backshop, the Deadline Newsroom.