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Kaspersky Anti-Virus 7.0
1.3.
Types of Threats
There are a vast number of threats to computer security today. This section will
review the threats that are blocked by Kaspersky Anti-Virus.
Worms
This category of malicious programs spreads itself largely by exploiting vul-
nerabilities in computer operating systems. The class was named for the
way that worms crawl from computer to computer, using networks and
email. This feature allows worms to spread themselves very rapidly.
Worms penetrate a computer, search for the network addresses of other
computers, and send a burst of self-made copies to these addresses. In ad-
dition, worms often utilize data from email client address books. Some of
these malicious programs occasionally create working files on system disks,
but they can run without any system resources except RAM.
Viruses
Viruses are programs which infect other files, adding their own code to them
to gain control of the infected files when they are opened. This simple defini-
tion explains the fundamental action performed by a virus
–
infection
.
Trojans
Trojans are programs which carry out unauthorized actions on computers,
such as deleting information on drives, making the system hang, stealing
confidential information, and so on. This class of malicious program is not a
virus in the traditional sense of the word, because it does not infect other
computers or data. Trojans cannot break into computers on their own and
are spread by hackers, who disguise them as regular software. The damage
that they inflict can greatly exceed that done by traditional virus attacks.
Recently, worms have been the commonest type of malicious program damaging
computer data, followed by viruses and Trojans. Some malicious programs com-
bine features of two or even three of these classes.
Adware
Adware comprises programs which are included in software, unknown to the
user, which is designed to display advertisements. Adware is usually built in-
to software that is distributed free. The advertisement is situated in the pro-
gram interface. These programs also frequently collect personal data on the
user and send it back to their developer, change browser settings (start
page and search pages, security levels, etc.) and create traffic that the user
cannot control. This can lead to a security breach and to direct financial
losses.
