Computer Virus Nighmares
Computer viruses are called viruses due to their similarities
with biological viruses. In the same way that biological viruses
enter the body and infect cells, computer viruses get into computers
and infect files. Both types of virus can replicate themselves and
spread, passing the infection from one infected system to another.
Also, just as a biological virus is a microorganism, computer viruses
are micro-programs.
In addition to replicating, a virus is generally programmed to deliver
a payload. Some computer viruses are just annoying and might display
a message on a trigger date. Some, however, are programmed to damage
data by corrupting programs, deleting files, or reformatting disks. Here is an example
of a recent rampant virus received as an Email.
The best definition of a virus is that it is a piece
of programming code usually disguised as something else that causes
some unexpected and usually undesirable event. A computer virus
is often designed so that it is automatically spread to other computer
users. Viruses can be transmitted as attachments to an email note,
as downloads, or it could be present on a diskette or CD. The source
of the email note, downloaded file, or CD you have received is often
unaware of the virus. Some viruses wreak havoc as soon as their
code is executed; other viruses lie dormant until circumstances
cause their code to be executed by the computer. Some viruses are
playful in intent and effect ("Happy Birthday, Gertrude")
and some can be quite harmful erasing data or causing your hard
disk to require reformatting.
The effects of the viruses vary enormously. A virus
can damage or delete data stored in a computer, use your computer
to spread more viruses or disable another computer, cause the infected
computer to crash or it may just display messages on the screen.
In addition to their transmission techniques, computer viruses also
use evasion techniques. This means that the virus has techniques
or a defense system that makes it difficult to detect and helps
it avoid any action taken against it. Some even attempt to disable
your Antivirus software. You are running Antivirus software, aren't
you?
Here is an example of just how fast a virus can spread. One of the
fastest spreading computer viruses was the one known as the "Slammer
Worm" It started when someone sent some code to a SQL server
where it snuck in through an open unprotected port. Once it was
in that server, the Slammer generated a set of random Internet addresses
and scanned them for other unprotected computers. Then it infected
them. From the computers it infected, it generated more IP addresses,
scanned them and infected them. Seems like a nightmare doesn't it?
The Slammer worm was relentless. In the first minute of existence,
it doubled the number of machines that it infected every 8.5 seconds.
In just three minutes it was scanning 55 million targets per second!
Within 10-minutes, 90 percent of all unprotected computers in the
world were infected. Luckily that is all that it did was spread.
What a nightmare it would have been if it carried a payload that
actually damaged computers.
You can help protect your computer from a virus attack
by "inoculating" it with antivirus software. Just remember
that, like many vaccination shots, one is not enough. You will need
to get regular boosters. In this case, that simply means updating
your antivirus software regularly. These updates are generally available
on a subscription basis from your antivirus vendor. Stay up to date
on any Internet Virus Information on our Virus
Resource page.
It is not just
having the antivirus program that is important, you also need to
keep it updated. There are new computer viruses reported daily and
the antivirus security companies usually update their virus protection
files daily. But amazingly enough, there are still viruses going
around the Internet that started over a year ago. The only way that
these viruses could still be spreading is because there are a lot
of people with computers that just aren't running Antivirus software
or not keeping it updated.
Although it is good practice, simply not opening email
from someone that you don't know isn't enough protection either
for two reasons. Number one is that the person sending you the email
may be somebody you know but his or her computer may be infected
and they don't know it. Another reason is that the mail may have
a familiar address because the address was spoofed right out of
your address book. There are other forms of viruses called worms
or trojan horses that get into your system by other means than email.
For example; the Blaster Worm scoured the Internet and infected
millions of computers by entering through an unprotected port of
unprotected computers. Yes they are sneaky. Good, updated antivirus
software is the only defense against these nightmarish creatures.
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