User guide

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If a file on your computer is detected as a Trojan, it is advisable to delete it, since it most likely contains nothing but
malicious code.
6.1.4 Rootkits
Rootkits are malicious programs that grant Internet attackers unlimited access to a system, while concealing their
presence. Rootkits, after accessing a system (usually exploiting a system vulnerability), use functions in the
operating system to avoid detection by antivirus software: they conceal processes, files and Windows registry data.
For this reason, it is almost impossible to detect them using ordinary testing techniques.
There are two levels of detection to prevent rootkits:
1. When they try to access a system: They are still not present, and are therefore inactive. Most antivirus systems
are able to eliminate rootkits at this level (assuming that they actually detect such files as being infected).
2. When they are hidden from the usual testing: ESET Smart Security users have the advantage of Anti-Stealth
technology, which is also able to detect and eliminate active rootkits.
6.1.5 Adware
Adware is a short for advertising-supported software. Programs displaying advertising material fall under this
category. Adware applications often automatically open a new pop-up window containing advertisements in an
Internet browser, or change the browser’s home page. Adware is frequently bundled with freeware programs,
allowing their creators to cover development costs of their (usually useful) applications.
Adware itself is not dangerous – users will only be bothered with advertisements. Its danger lies in the fact that
adware may also perform tracking functions (as spyware does).
If you decide to use a freeware product, please pay particular attention to the installation program. The installer
will most likely notify you of the installation of an extra adware program. Often you will be allowed to cancel it and
install the program without adware.
Some programs will not install without adware, or their functionality will be limited. This means that adware may
often access the system in a “legal” way, because users have agreed to it. In this case, it is better to be safe than
sorry.If there is a file detected as adware on your computer, it is advisable to delete it, since there is a high
probability that it contains malicious code.
6.1.6 Spyware
This category covers all applications which send private information without user consent/awareness. Spyware uses
tracking functions to send various statistical data such as a list of visited websites, email addresses from the user‘s
contact list, or a list of recorded keystrokes.
The authors of spyware claim that these techniques aim to find out more about users’ needs and interests and
allow better-targeted advertisement. The problem is that there is no clear distinction between useful and
malicious applications and no one can be sure that the retrieved information will not be misused. The data
obtained by spyware applications may contain security codes, PINs, bank account numbers, etc. Spyware is often
bundled with free versions of a program by its author in order to generate revenue or to offer an incentive for
purchasing the software. Often, users are informed of the presence of spyware during a program‘s installation to
give them an incentive to upgrade to a paid version without it.
Examples of well-known freeware products which come bundled with spyware are client applications of P2P (peer-
to-peer) networks. Spyfalcon or Spy Sheriff (and many more) belong to a specific spyware subcategory – they
appear to be antispyware programs, but in fact they are spyware programs themselves.
If a file is detected as spyware on your computer, it is advisable to delete it, since there is a high probability that it
contains malicious code.