Malware

Spyware

 Spyware is a form of software that is installed on your computer without your knowledge or permission and monitors you internet activity.  This info is usually sent to advertising agencies of some kind, and they then tailor the pop-ups you see based on your past behavior.  Such activity can seriously slow down your machine, and may result in system crashes.  There is also the danger that sensitive or private information will be gathered in this way.

For more info on Spyware and for anti-spyware software, click here.

"Keystroke Logger"

One of the more sinister things that you could inadvertently download onto you computer just by following unfriendly links, clicking on evil pop-ups, or opening attachments sent in malevolent emails.  Such software actually records which keys are pressed on your keyboard and sends a report to the bad-guys.  So much for password protection.

Viruses, Worms, and Trojan Horses

Viruses are pieces of code that alter the behavior of a computer without the knowledge or permission of the computer's owner or user.  They can  cause memory loss, program failure, or cause your computer to behave in strange and possibly detrimental ways.  They execute themselves and replicate.  One infected computer can pass the virus to an entire network (such as the university's).

Worms are similar to viruses in that they are human written malicious software ("malware"), but are structured differently and differ in their mode of reproduction.  Whereas a virus is attached to a file or program, a worm is self contained.  Viruses often result in the infected computer behaving erratically, while a worm may operate in a very specific, coordinated way (e.g. acting as a "Keystroke Logger", discussed above).  When a worm exists on a computer, it scans the network to which the computer is connected.  It checks the other computers on this network for specific vulnerabilities that will allow the worm to reproduce itself across the network.  If computers with the proper vulnerabilities are detected, the worm copies itself onto these computers and begins scanning from them as well.  This reproductive function is separate from other malicious actions the worm may undertake on the host machine (e.g. fascilitating data theft).

Trojan horses are distinct form worms and viruses in that they do not reproduce.  They are malicious programs disguised as something benign.  Once executed, they can cause data loss or theft.  Being that these do not reproduce, you actually have to download them onto your computer and run them for them to hurt you.  (Remember that they claim to be something desirable.)  A healthy level of paranoia will prevent these malware denizens from ever troubling you. Simply never download or execute any program unless you are absolutely certain as to the integrity of the source.

See the main CU ITS site for more info.