What is Spyware?
Spyware is one of the subclasses of the malicious software based on spying, collecting data about computer resources or user's personal information without their knowledge.
This type can't be definitely rated as viruses because such programs can't reproduce themselves and damage files. However, their aims are rather harmful. Apart from various marketing researches and advertising spyware can also make a hacker or DDoS attack much easier. Moreover, this kind of malware often masquerades as the necessary update for an installed program.
The programs of the kind have a wide range of various tasks, for example:
- saving screenshots, remembering the keys a user has pressed on the keyboard;
- monitoring system security parameters;
- detecting information about software or web sites visited by a user.
All collected information is sent to the developers of the spyware. Besides, users are claimed to download spyware voluntary. Developers may be right when saying so because the majority of users click on I Accept button without even reading the agreement. Spyware may be distributed along with some useful program; even more, this fact may be stated in the user agreement. Such programs are also spread via the Internet.
As in case with malware, there is no commonly used classification of the spyware. But it is possible to single out some characteristic features:
- a malicious program is installed on the user's computer without their awareness and, of course, without being put in the Add/Remove Programs list in order to make uninstalling impossible. It also can be installed as a component of a useful program.
- hidden download of a program into the main memory in the process of computer boot. Today there exist technologies implying launching two processes instead of one able to start one another in case one of them is stopped by Windows Task.
- performing certain functions without user's permission (like transmitting or receiving data via the net);
- independent downloading of updates or other programs initiated by the program without user's knowledge;
- the program changes system or network settings or creates difficulties in other programs functioning without user's participation;
- secret changing of the information or its streams (for example, ads or new hyperlinks on the downloaded web pages).
Spyware can be divided into the following categories for convenience:
1. Tracking: programs that perform surveillance.
2. Keyloggers are programs monitoring and controlling any key pressing on the keyboard.
3. Screen scraper make screen captures.
4. Other harmful programs display ads, download software, various add-ins and browser or operating system applications, etc.
There are several types of frauds using various mechanisms:
- on-line hacker attacks
As a rule they are aimed at stealing of user's personal data (credit card numbers, account details etc.);
- marketing organizations
They are also interested in personal information (email address, key words for search engines, history of Internet purchases, etc.).
- Inside espionage
It includes those people who have legal physical access to a computer or the whole network. – data collected directly by the spyware program
They can control practically any user's activity on the computer (screenshots, network traffic, buffer content, browser history, email and so on).
However, such spy programs don't send passwords and don't provide remote access to computers for their developers. But their monitoring user's computer gives data about the duration and date of its work in the Internet, list of visited sites, etc.