You've Been Hacked

Note: Please check out the ACCC Web page based on this newsletter issue: Connecting from Home - Using Cable or DSL and specifically Securing Your Internet Connection. We keep it updated.

Congratulations, you've been hacked!

It's easy to think that no one could possibly be interested in your poor, slow, little 486 or Pentium 90 (or iMac, for that matter), but that's simply not the case. Having a fast Internet connection that's "always on" when you want to surf the Web is great for you, but it's also great for hackers from around the world who have nothing better to do than sweep through thousands of random IP addresses looking for machines that they can exploit.

And what they can do is really quite scary. Without any visible sign or warning, hackers can infiltrate your system to obtain personal information about you or to use your computer to disguise themselves when they attack other machines. Remember last February when CNN, eBay, and Yahoo! were crashed by denial of service (DOS) attacks? Those attacks were made using "zombie computers," academic and corporate computers that had been hacked into from the outside twice: once to install attack software and a second time to initiate the attack.

While it's likely that nothing this drastic has happened to your computer yet, it's certain that you've been probed. My PC at work is probed at least once a day. You really need to take care of this.

The first thing to do to protect your always-on-the-Internet personal computer from attack from the outside is turn sharing off on all your disk drives and printers. And you must do it right now. (Unless you have a LAN in your house, of course; in that case, you should put a password on all your drives.)

This is particularly important if you have a cable modem, because your computer is on a LAN with your neighbors.

To turn off file and printer sharing in Windows: Double-click the My Computer icon on your desktop. Then right-click on the name of a drive, select Properties, click the Sharing tab, then click the Not Shared radio button. Repeat for each drive. Then double-click the Printers folder and repeat the same process for each printer.

To turn off file sharing in Macs: Open the Sharing Setup control panel. In the File Sharing section, you should see the message "File sharing is off" with a Start button beside it. If you see a Stop button instead, click it. A dialog box will open asking "How many minutes until file sharing is disabled?" Select 0 and click OK.

If you have an always-on Internet connection, via a cable modem or DSL or IDSN line, you must also install a personal firewall (a network protection tool that guards against and reports intrusions on your computer from the outside), and you must keep it running at all times.

To get an idea of what the firewall will do for you, use Security Space's Desktop Audit before and after you install the firewall. This service checks the security of your computer's connection to the Internet by sending it various connection requests. Visit: Security Space's Desktop Audit and select Desktop Audit. You have to register before you can run an audit. To register, fill out the New User box on the Desktop Audit page, click the Register button, then follow their instructions.

Believe me, it does. Or don't believe me. Download and install ZoneAlarm or BlackICE Basic and run it for a week or so. That will convince you.

Comments are welcome; send them to
Judith Grobe Sachs, judygs@uic.edu