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Learning Guide: Spyware

Table of Contents:

What is spyware?
Why spyware isn't just a home-user problem
How spyware gets in your computer
How you can prevent spyware
How you can clean up spyware

What is spyware? Back to table of contents 

In general, spyware is any technology that aids in gathering information about a person or organization without their knowledge. Internet advertising (adware) has been criticized for sometimes including code that tracks a user's personal information and passes it on to third parties without the user's authorization or knowledge. This practice has been dubbed spyware and has prompted an outcry from computer security and privacy advocates, including the Electronic Privacy Information Center.

Noted privacy software expert Steve Gibson of Gibson Research explains: "Spyware is any software that employs a user's Internet connection in the background (the so-called 'backchannel') without their knowledge or explicit permission. Silent background use of an Internet 'backchannel' connection must be preceded by a complete and truthful disclosure of proposed backchannel usage, followed by the receipt of explicit, informed consent for such use. Any software communicating across the Internet absent of these elements is guilty of information theft and is properly and rightfully termed: Spyware."

Spyware doesn't actually attempt to "take over" your computer, but it does try to do certain things you probably won't like. Here are some common signs that you have been infected:

    • Your PC is running unusually slow.

    • Ads are popping up even when your browser isn't running.

    • Your home page has been hijacked.

    • Antispyware and/or antivirus applications aren't working correctly. Some spyware programs will sabotage the programs designed to detect and eliminate them.

    • There's been a dramatic increase in your network's traffic, eating up bandwidth and crippling performance.

Read our complete definition. has a definition of spyware.

Top ten spyware threats
This list describes the ten spyware threats most frequently identified by Webroot's Spy Audit.

Spyware Guide
Spyware guide has an extensive list of software that has been identified as spyware.

More resources about spyware, adware and Trojans from TechTarget.

Spyware legislation sparks concern
This installment in a two-part series examines legislative effectiveness in handling spyware.

Fight spyware
A whole new category of software has exploded into life lately, with intentions that are far from honorable. These programs, called adbots , media plug-ins, backdoor Santas or Trojans, are known collectively as spyware.

Why spyware isn't just a home-user problem Back to table of contents 

Spyware is no longer just a home user issue. Spyware in the enterprise is already costing companies millions of dollars in lost time and productivity and money spent to address it, and it's expected to get worse. IDC, a top research and advisory company for the IT and telecommunications industries, reported that $12 million was spent in 2003 on antispyware solutions, but that number is predicted to increase by 260 percent within the next five years. Webroot, creator of antispyware program Corporate SpyAudit, scanned more than 10,000 computers in over 4,100 companies over the course of six months. On average, it identified 20 pieces of spyware per corporate computer.

Spyware, spyware everywhere
An eye-opening look at the spyware phenomenon. Find out just how seriously you should take it.

The nasty truth about spyware
While spyware programs are nothing new, they continue to grow in virulence and sophistication. Anyone that uses a computer and the Internet should be aware of the risk these programs present.

Spyware: Bigger concern than IT admins realize
IT managers should be more aware of the hazards of spyware, a report suggests.

Malware Spotlight: Spyware
Get help recognizing spyware problems and preventing them from infecting Windows.

Spyware: The First Thing You Need to Know Is That You Probably Have It : White Paper
Spyware-software installed on a computer usually without the user's knowledge or permission - along with adware and other similar software, gathers information and sends it back to the advertiser who initiated it or other interested parties.

The dangers of spyware
This white paper focuses on an aspect often overlooked by users, the information-gathering functionaility of spyware. In addition to explaining what spyware is and what publishers use it for, it also provides IT professionals with insight into why spyware appeals to users.

How spyware fits into defense-in-depth
Learn how spyware can compromise your security strategy.

Spyware - It's on Your Network and Hurting Your Business: Data Sheet
This paper will provide you with an understanding of what spyware is, how it accesses your network, and the damage that spyware can cause to your network and organization productivity.

Spyware becoming big network headache
Network managers report spyware incidents rising sharply in recent months and say it could soon qualify as the top security headache in the corporate world.

How spyware gets in your computer Back to table of contents 

Spyware can get in a computer as a software virus or as the result of installing a new program. Data collecting programs that are installed with the user's knowledge are not, properly speaking, spyware, if the user fully understands what data is being collected and with whom it is being shared. However, spyware is often installed without the user's consent, as a drive-by download, or as the result of clicking some option in a deceptive pop-up window.

Can a firewall prevent spyware from entering the internal network?
Expert Serdar Yegulalp explains why a firewall can not prevent spyware from entering an internal server.

The Spying Game: How Spyware Threatens Corporate Security : White Paper
Describes the ways spyware can install itself.

Separating 'bad' spyware from 'good'
Symantec hammers out a system to measure the risk impact of spyware it detects, so users can decide what gets to inboxes.

Spy Fighters: Managing spyware protection for remote employees
This remote access engineer and reader explains how he centrally manages spyware protection and cleansing for 45,000 employees' work and home machines.

One company's spyware is another's monitoring tool
Enterprises often take steps to protect against spyware, in much the same way they do against viruses and worms. But some companies also use spyware to monitor employees suspected of illicit behavior.

Rousting spyware
Spyware -- a longstanding issue with privacy advocates and legislators -- is drawing increasing attention from security personnel who must contend with the security and productivity problems it poses.

Tools for combating spyware in the enterprise
Learn how the threat of spyware might impact your enterprise and what you can do about it.

Cost-effective remote end point protection: Against Trojans, spyware and other pests
Any network is only as secure as its weakest node. This paper illustrates the security threats posed by remote workers that use VPN tunnels to access corporate networks and the business risk of leaving these "remote end points " inadequately protected.

Microsoft warns of spyware's impact on SP2
Microsoft is urging users to scan their PCs for spyware before downloading Windows XP Service Pack 2. For some, spyware programs are causing machines to lock up during an SP2 installation.

Fighting browser-based spyware
Today's browser battle is being fought between forces that want to have control over users' browsers: users and administrators versus spyware. If a user merely surfs to the wrong Web site, aggressive malware can install itself on the users' box, steal information and possibly give an attacker remote control of the system.

U.S. seeks to stop a brazen spyware operation
In what the U.S. Federal Trade Commission called the ultimate in "online chutzpah," a group selling antispyware under the Spy Wiper and Spy Deleter labels actually loaded spyware onto unsuspecting users' computers.

How you can prevent spyware Back to table of contents 

The best defense against spyware and other unwanted software is not to download it in the first place. Some experts recommend that you change browsers periodically or simply avoid using Internet Explorer. Here are a few helpful tips from Microsoft that can help protect you from downloading potentially unwanted programs:

    • Only download programs from Web sites you trust.

    • Read all security warnings, license agreements and privacy statements associated with any downloads.

    • Never click "agree" or "OK" to close a window. Instead, click the red "x" in the corner of the window or press the Alt + F4 buttons on your keyboard to close a window.

    • Be cautious about using "free" music and movie file-sharing programs, and be sure you clearly understand all of the software packaged with those programs.

Show me everything on Spyware Protection

Reduce spyware infections by educating users
Suggestions for reducing spyware, adware and malware on users' PCs.

There is no anti-spyware silver bullet
Meta Group says that unless better enterprise-class tools emerge for spyware removal, then the threat to enterprise security will only increase over the next few years.

Win2000 malware guide: spotlight spyware
Get help recognizing spyware problems and preventing them from infecting Windows with the following collection of editor-selected spyware articles and tips from

Spyware Prevention for the Enterprise : White Paper
Spyware prevention at the gateway is critical to defend against surreptitious installation and information gathering techniques.

Spyware prevention strategies: From hardening to avoiding IE
Your Windows systems may appear to be clean of spyware, but what's to prevent this nuisance from hitting you next -- or striking again?

Will spyware wither under new enterprise tools?
A number of new tools have emerged to detect and eradicate spyware, but their long-term effectiveness remains to be seen

Spyware Product Details and Product Information
Research the latest Spyware tools, technologies and techniques and compare products from many vendors.

Anti-Spyware Software: Securing the Corporate Network : White Paper
In the last few years, multiple anti-spyware products have been introduced to the marketplace; however, these tools have been designed for desktop users and have not been scalable to corporations.

Spy Fighters: Keeping student laptops spyware-free
How do you keep 750 laptops belonging to K-12 students clean of spyware? It's not easy. One network administrator shares her techniques.

Spy Fighters: Lose Internet Explorer to solve spyware problems
To meet his security needs, this TechTarget reader gave up on most Microsoft products a long time ago. Find out what he says about Windows vulnerabilities and how to ultimately protect your systems from spyware.

Spyware prevention strategies
Spyware is one of the biggest security problems affecting Windows desktops. How can you stop it from piggybacking and hindering your Internet Explorer use? Get tips here.

Get rid of spyware and popups
Get advice on how to cut down on spyware pop-ups from TechTarget contributor Serdar Yegulalp.

Systems to reduce Spyware, Adware and Malware
Hi all, I would like to implement something to reduce the chances for users to be hit by Spyware, Adware and Malware while surfing the internet. What kind of systems would you recommend?

Running more than one anti-spyware tool
I've recently been talking to some IT security professionals about the absence of a single tool that can fix all of their spyware problems. It seems that to get most of the spyware off of a Windows system you need to run more than one spyware checker. True?

Tip #8: Spyware block-and-tackle tactics
Stop spyware from infecting your desktops with help from these three spyware prevention strategies, from blocking bad objects to restricting browsing habits.

Strategies for battling spyware
If you think your AV has you protected -- think again -- and consider these strategies.

New spyware options for enterprises
Vendors are now beginning to address the spyware problems faced by business users.

Protect against spyware
This tip gives you some ideas of how you can try to prevent someone from downloading a piece of spyware from the Internet onto your network.

How you can clean up spyware Back to table of contents 

Once you've been infected, the spyware program may sabatoge your efforts to clean it up. editors recommend Microsoft's antispyware software. Many experts recommend using more than one antispyware program.

Show me everything on Spyware Cleansing

Spyware management forum
If you need help with fixing a problem caused by spyware or a browser hijacker, you can post your questions in the spyware management forum.

Spyware removal
Which tool should you use to monitor and remove spyware?

Spy Fighters: Antispyware lessons learned by TechTarget readers
When asked which antispyware solutions work best, TechTarget readers have a lot to say. A group of true spy fighters share their nightmares, opinions and advice on beating spyware.

How to Eliminate Spyware to Protect Your Business : White Paper
IT security experts warn that spyware is rapidly moving from personal computers to business networks connected to the Internet.

Spy Fighters: Spyware battle that took six tools to win
One TechTarget reader shared this story about a major spyware battle he fought and finally won -- using six different antispyware tools.

Spy Fighters: A more secure Internet is the only true spyware solution
This TechTarget reader describes a problem he's had with one particular antispyware solution, and explains what's needed to truly solve spyware problems.

Study: Tools let spyware slip through cracks
A U.S. researcher claims that even the best antispyware tools miss 25% of the criticial files and registries associated with malicious or intrusive programs.

Cleaning up unwanted spyware and parasites
If you have spyware on your system, don't panic. This article takes you through the steps of spyware cleaning and teaches you what to do to prevent future spyware attacks.

This was last updated in September 2005


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