Spyware

Spyware is a specific type of malware designed to gather information about a person or an organization. This data is then sent to another entity without the user's knowledge. Such behavior harms users by violating their privacy or endangering the security of their devices.

Because these behaviors appear in both malicious programs and some legitimate software, providing a precise definition is a difficult task. It is often associated with advertising and can affect computers, websites, and even hardware devices.

The mechanism of spyware involves several steps to ensure it remains active and hidden. First, the software installs itself on a device, often by using exploits in JavaScript or web browsers. In some cases, it uses the Windows Registry to ensure it runs automatically when the computer boots up. The Registry is a part of the operating system that stores settings. Spyware can link itself to multiple locations in the Registry to prevent removal. If a user deletes one link, the spyware periodically checks and automatically restores it. Once active, it uses a "backchannel," or an internet connection, to send data back to its creators without explicit permission.

Spyware is generally classified into four main types. These include adware, which focuses on advertisements, and system monitors that watch user activity. It also includes web tracking to follow internet movements and trojans, which are programs that appear legitimate but hide malicious functions. Other specific forms include keyloggers, which record every keystroke made on a keyboard, and rootkits. Some software also features digital rights management (DRM) capabilities that "phone home" to a central server. These categories are not mutually exclusive, and they often use similar tactics to attack networks and avoid detection.

The history of spyware is tied to the rise of e-commerce in the mid-1990s. As companies like Amazon.com and CDNOW.com grew, competition for customers intensified. The first recorded use of the term "spyware" occurred on October 16, 1995, in a Usenet post. In the early 2000s, Steve Gibson provided a foundational description of the threat. He defined it as software using a user's internet connection in the background without permission. In 2000, a notable incident involved educational software called Reader Rabbit. It was discovered that the software was surreptitiously sending data back to the Mattel toy company.

By the mid-2000s, spyware had become a massive security threat. A 2005 study by AOL and the National Cyber-Security Alliance revealed how widespread the issue was. The study found that 61 percent of surveyed computers were infected with some form of spyware. Even more striking were the numbers regarding user awareness. Approximately 92 percent of users with spyware did not know it was present. Furthermore, 91 percent of those users reported they had never given permission for the installation.

One major driver for spyware is the industry of targeted advertising. Advertisers discovered they could build detailed user profiles by collecting data on browsing habits. This allowed them to show ads tailored to a person's specific interests. This created a gray area where the line between adware and spyware began to dissolve. Many software developers began offering products "free of charge" to users. While this sounds like a gift, it often expects information in return as compensation. This practice can lead to reduced system performance and unauthorized changes to browser settings.

To combat these threats, a specialized industry for anti-spyware tools has emerged. These tools work similarly to antivirus software by identifying programs using digital signatures. A signature is a specific piece of program code or an identifying attribute. However, this method only works for known programs, meaning new spyware can still go undetected. This leads to "false positives," where legitimate software is mistakenly flagged as spyware. Some dishonest companies even distribute fake anti-spyware tools. These fake tools claim to clean a computer but actually install more adware or spyware instead.