An introduction to computer viruses: problems and solutions
| DOI | https://doi.org/10.1108/07419051211280036 |
| Date | 14 September 2012 |
| Published date | 14 September 2012 |
| Pages | 8-12 |
| Author | Imran Khan |
| Subject Matter | Library & information science |
Introduction
The development of large-scale
complex campus networks needs to be
concerned with network security so
that the campus network remains stable.
In today’s information age, the pool of
information available continues to expand
logarithmically. Digital information has
transformed the way we create, transmit,
store, process and manipulate
information. All the electronic resources
and information are being stored in
computer systems for their retrieval and
dissemination. In today’s highly computer
dependant environment, computer
security is a major concern. The security
of computers is routinely threatened by
malicious programs such as computer
viruses, Trojan horses, worms and the like.
Once computers are infected these
programs may have the ability to
damage expensive computer hardware,
destroy valuable data, tie up limited
computing resources or compromise the
security of sensitive information. People
accumulate data from many sources using
various available electronic storage
devices such as USB drives, CD/DVD-
ROMs, etc. and then store the data on their
computers. Many people are not fully
computer literate and may be unaware of
the latest virus threats. When users move
or copy data from computer to computer
viruses can be transmitted via computer
systems, an internal network or the
internet. Once a computer system gets
infected with a virus, the data stored in it
becomes insecure and the system
becomes a source of infection to other
systems during the transfer of data.
Computer viruses and related
malware
A computer virus is a computer
program that can replicate itself and
infect a computer. The term “computer
virus” is also commonly but erroneously
used to refer to other types of malware,
adware, and spyware programs that do
not have this reproductive ability.
Malware includes worms, Trojans,
most rootkits, spyware, dishonest
adware, crimeware, and other
unwanted software, including true
viruses. Viruses are sometimes
confused with computer worms and
Trojan horses, which are technically
different. A worm can exploit security
vulnerabilities to spread itself to other
computers through networks, while a
Trojan is a program that appears
harmless but hides malicious functions.
Worms and Trojans, like viruses, may
harm a computer system’s data or
performance. A true virus can only
spread from one computer to another
(in some form of executable code) when
its host is taken to the target computer;
for instance because a user sent it over
a network or the internet, or carried it
on a removable medium such as a
floppy disk, CD, DVD, or USB drive.
Transmission of viruses can increase by
infecting files on a network file system
or a file system that is accessed by
another computer. Computer viruses
were labeled as viruses because of the
fact that they are similar to biological
viruses in the aspect of multiplying
themselves. Similarly they find a host
and then infect and multiply themselves.
However, in both cases there must be a
cause in order for the problem to begin.
Some viruses and other malware have
symptoms noticeable to the computer
user, but many are surreptitious and go
unnoticed.
There are different types of computer
viruses and each type has their own
unique features that differentiate
themselves from one another. Among
the different types of viruses the most
familiar ones are computer-based
viruses and internet-based viruses.
There are many subtle and obvious
distinctions that set the different typesof
computer viruses apart from one
another. Some of the more typical
viruses are described below.
“Resident viruses” exist in a
computer’s volatile memory (RAM).
From there it can overcome and
interrupt all of the operations executed
by the system like corrupting files and
programs that are opened, closed,
copied, renamed, etc. Examples of this
type of virus include Randex, CMJ,
Meve, and MrKlunky.
Multipartite viruses are distributed
through infected media and usually hide
in the memory. Gradually, the virus
moves to the boot sector of the hard
drive and infects executable files on the
hard drive and later across the computer
system.
“Direct action viruses” replicate and
take action when executed. When a
specific condition is met, the virus
comes into action and infects files in
the directory or folder that it is in and in
directories that are specified in the
AUTOEXEC.BAT file PATH. This
batch file is always located in the root
directory of the hard disk and carries out
certain operations when the computer is
booted.
“Overwrite viruses” are characterized
by the fact that they delete the information
contained in the files that it infects,
rendering them partially or totally
useless once they have been infected.
The only way to clean a file infected by
an overwrite virus is to delete the file
completely, thus losing the original
content. Examples of this virus include
Way, Trj.Reboot, Trivial.88.D.
“Boot sector viruses” affect the boot
sector of a floppy, USB or hard disk
drive. This is a crucial part of a disk, in
which information on the disk itself is
stored together with a program that
makes it possible to boot (start) the
8
Library Hi Tech News
Number 7 2012, pp. 8-12, qEmerald Group Publishing Limited, 0741-9058, DOI 10.1108/07419051211280036
An introduction to computer viruses: problems
and solutions
Imran Khan
To continue reading
Request your trial