Hardware Reference
In-Depth Information
get your usernames and passwords that way and use them to impersonate you. (See the
section “Identity Fraud and Social Engineering” earlier in this chapter.)
Trojan horse programs don't replicate themselves, so they aren't viruses, technically
speaking. The most common way that Trojan horse programs spread is via worms. (See the
next section.) Most antivirus programs can detect and remove Trojan horses.
Worms
Worms
are self-transporting applications that carry an active payload, such as a Trojan
horse or a virus. Worms can be active or passive: active worms self-transport without human
intervention, whereas passive worms rely on the user's innocence to transport themselves
from one location to another, normally through email or social engineering. Active worms
use email, vulnerabilities in your OS, the Web, and DNS servers to move their payload
around a network infrastructure. Most antivirus programs can detect and remove worms.
Adware
Adware
is a category of application that displays un-asked-for ads on your computer. The
most common type of adware comes in the form of an add-on toolbar for your web browser
that supposedly provides “advanced” or “helpful” search services, but that also has the side
effect of causing pop-up ads to appear whenever you use your web browser. Adware makers
make money when people click the ads they display.
Strictly speaking, not all adware is illegal, and not all adware makers are involved
in criminal activity. If you're seduced into downloading a particular web toolbar or
application, and then you aren't happy with what it does, or there are too many ads to
make it worth the value you're getting from it, you're free to remove it. Removal may not
be easy, though; the uninstall option for the toolbar may or may not appear in the Control
Panel in Windows, and you may need to connect to a website or go through some extra
steps to complete the removal.
Some adware is an out-and-out annoyance, with no pretense of being anything else.
Such programs are typically very diffi cult to remove, much like a virus infection. Your
antivirus software may be of some help; you also may need to do a web search on the
removal process to fi nd Registry-editing instructions to help you stamp out the adware.
Spyware
Spyware
is software that (usually secretly) records your computer usage. Keyloggers are a
form of spyware; so are programs that track the websites you visit and what ads you click
and send that information back to their owners. Spyware makers get revenue from collecting
consumer marketing data, either specifi cally about you or about all users in general. Most
spyware is illegal, works surreptitiously, and can be diffi cult to remove.
Spyware isn't self-replicating, and it relies on low-level social engineering to spread.
The most common way to get infected with spyware is to install a free application from
