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Recognizing and Avoiding Spyware
What is spyware?
Despite its name, the term "spyware" doesn't refer to
something used by undercover operatives, but rather by the advertising industry.
In fact, spyware is also known as "adware." It refers to a category
of software that, when installed on your computer, may send you pop-up ads,
redirect your browser to certain web sites, or monitor the web sites that
you visit. Some extreme, invasive versions of spyware may track exactly what
keys you type.
Because of the extra processing, spyware may cause your computer to become slow or sluggish. There are also privacy implications:
- What information is being gathered?
- Who is receiving it?
- How is it being used?
How do you know if there is spyware on your computer?
The following symptoms may indicate that spyware is installed
on your computer:
- you are subject to endless pop-up windows
- you are redirected to web sites other than the one you typed into your browser
- new, unexpected toolbars appear in your web browser
- new, unexpected icons appear in the task tray at the bottom of your screen
- your browser's home page suddenly changed
- the search engine your browser opens when you click "search" has been changed
- certain keys fail to work in your browser (e.g., the tab key doesn't work when you are moving to the next field within a form)
- random Windows error messages begin to appear
- your computer suddenly seems very slow when opening programs or processing tasks (saving files, etc.)
How can you prevent spyware from installing on
your computer?
To avoid unintentionally installing it yourself, follow these good
security practices:
- Don't click on links within pop-up windows - Because pop-up windows are often a product of spyware, clicking on the window may install spyware software on your computer. To close the pop-up window, click on the "X" icon in the titlebar instead of a "close" link within the window.
- Choose "no" when asked unexpected questions - Be wary of unexpected dialog boxes asking whether you want to run a particular program or perform another type of task. Always select "no" or "cancel," or close the dialog box by clicking the "X" icon in the titlebar.
- Be wary of free downloadable software - There are many sites that offer customized toolbars or other features that appeal to users. Don't download programs from sites you don't trust, and realize that you may be exposing your computer to spyware by downloading some of these programs.
- Don't follow email links claiming to offer anti-spyware software - Like email viruses, the links may serve the opposite purpose and actually install the spyware it claims to be eliminating.
As an additional good security practice, especially if you are concerned that you might have spyware on your machine and want to minimize the impact, consider taking the following action:
- Adjust your browser preferences to limit pop-up windows and
cookies - Pop-up windows are often generated by some kind
of scripting or active content. Adjusting the settings within your
browser to reduce or prevent scripting or active content may reduce
the number of pop-up windows that appear. Some browsers offer a specific
option to block or limit pop-up windows. Certain types of cookies are
sometimes considered spyware because they reveal what web pages you
have visited. You can adjust your privacy settings to only allow cookies
for the web site you are visiting (see Browsing
Safely: Understanding Active Content and Cookies for more information).
February 9, 2005
National Webcast Initiative
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