Glossary; Types Of Infiltrations; Viruses; Worms - ESET CYBERSECURITY Installation Manual

than other types of malware.
A worm activated in a system can cause a number of
inconveniences: It can delete files, degrade system
performance, or even deactivate programs. The nature
of a computer worm qualifies it as a "means of transport"
for other types of infiltrations.
If your computer is infected with a worm, we
recommend you delete the infected files because they
likely contain malicious code.
Examples of well-known worms are: Lovsan/Blaster,
Stration/Warezov, Bagle and Netsky.

6.1.3 Trojan horses

Historically, computer trojan horses have been defined
as a class of infiltrations which attempt to present
themselves as useful programs, tricking users into
letting them run. Today, there is no longer a need for
trojan horses to disguise themselves. Their sole purpose
is to infiltrate as easily as possible and accomplish their
malicious goals. "Trojan horse" has become a very
general term describing any infiltration not falling under
any specific class of infiltration.
Since this is a very broad category, it is often divided into
many subcategories:
Downloader – A malicious program with the ability to
download other infiltrations from the Internet.
Dropper – A type of trojan horse designed to drop
other types of malware onto compromised
computers.
Backdoor – An application which communicates with
remote attackers, allowing them to gain access to a
system and to take control of it.
Keylogger – (keystroke logger) – A program which
records each keystroke that a user types and sends
the information to remote attackers.
Dialer – Dialers are programs designed to connect to
premium-rate numbers. It is almost impossible for a
user to notice that a new connection was created.
Dialers can only cause damage to users with dial-up
modems, which are no longer regularly used.
Trojan horses usually take the form of executable files.
If a file on your computer is detected as a trojan horse,
we recommend deleting it, since it most likely contains
malicious code.
Examples of well-known trojans are: NetBus,
Trojandownloader.Small.ZL, Slapper.

6.1.4 Adware

Adware is a shortened term 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 creators of freeware
programs to cover development costs of their (usually
useful) applications.
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