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 September 2003 Dan Mooney - Gisèle Winger - Ric Woltz | Virus Information | Antivirus Software | What is a Worm? | Virus Hoaxes | Fast Viruses | Are You Vulnerable? As many of
you are aware, over the last several weeks, the
GECDSB computer network was infected with both the
SOBIG and MSBlast worms. It seems like an ideal
time to remind everyone that you really need to
make sure that your home computer is protected.
Viruses are not accidents of programming, they are
designed to inflict damage, in some cases minor,
and irritating, and in others, they can destroy
your hard drive causing you to lose everything
loaded and saved. The thought of losing all of my
report cards and comments would be incentive enough
to make me invest in protection. Viruses and worms
are spread through the internet and email. Any time
that you download, you put yourself at risk.
Although the vast majority of these threats are
designed for WIndows machines, Macs are also at
vulnerable. In First
Class, opening an email will NOT allow a virus to
be downloaded. You must open an attachment in the
email in order to be at risk. Downloading any file
from the internet, can put you at risk. The best
protection for your computer is an up-to-date virus
checking program.
The best
protection against a virus is to buy anti-virus
software that can screen e-mail attachments and
also check all of your files periodically and
remove any viruses that are found. Unfortunately,
the Ministry licence for Command Antivirus, for
Windows machines, expired at the end of August. The
new licence for Macafee, and the Norton licence for
Macs do not allow for teacher take home use, so we
will no longer be able to post the updates to the
virus definitions in the First Class conference.
Every teacher should protect their computer, by
purchasing a good piece of VIrus Checking software,
and keeping it updated. All of the better virus
software will have an automated updater, which is
the best way to keep current, as new viruses are
developed on a regular basis. Antivirus software is
worthless if it is not kept up to date. Antivirus
software is also one of the few cases where more is
not better. Virus software, by necessity, is
invasive. It must search every file and folder on
your computer looking for dangerous
code. If
you have several virus checkers running, they will
scan the virus definitions in each other, and will
often find suspect code, and can in some instances
damage the virus checker in an effort to clean
files. Picking the
best antivirus software is as much individual
preference as trying to pick the best word
processor. When selecting one, make sure that
regular updates are available and easy to install.
Many of the best packages make updates available
daily.
A worm is a
self-replicating virus that does not alter files
but resides in active memory and duplicates itself.
Worms use parts of an operating system that are
automatic and usually invisible to the user. It is
common for worms to be noticed only when their
uncontrolled replication consumes system resources,
slowing or halting other
tasks.
What
is a Virus? A virus is a
piece of programming code, usually disguised as
something else, that causes some unexpected and
usually undesirable event. A virus is often
designed so that it is automatically spread to
other computer users. Viruses can be transmitted as
attachments to an e-mail note, as downloads, or be
present on a diskette or CD. The source of the
e-mail note, downloaded file, or diskette you've
received is often unaware of the virus. Some
viruses kick into effect as soon as their code is
executed; other viruses lie dormant until
circumstances cause their code to be executed by
the computer. Generally,
there are three main classes of viruses:
File
infectors. Some file infector viruses attach
themselves to program files, usually selected .COM
or .EXE files. Some can infect any program for
which execution is requested, including .SYS, .OVL,
.PRG, and .MNU files. When the program is loaded,
the virus is loaded as well. Other file infector
viruses arrive as wholly-contained programs or
scripts sent as an attachment to an e-mail note.
System or
boot-record infectors. These viruses infect
executable code found in certain system areas on a
disk. They attach to the DOS boot sector on
diskettes or the Master Boot Record on hard
disks. Macro
viruses. These are among the most common viruses,
and they tend to do the least damage. Macro viruses
infect your Microsoft Word application and
typically insert unwanted words or phrases.
From time to
time, you may get an e-mail message warning of a
new virus. Unless the warning is from a source you
recognize, chances are good that the warning is a
virus hoax. Even if you know the source of the
email, we often get warnings from well intentioned
friends about new viruses. Before you forward a
warning, or before you act on the warning, visit
the Symantec
Security Response - Hoax
Page,
and make sure it is a legitimate virus. Many of
theses hoaxes cause damage by getting you to delete
files that are essential to the proper functioning
or your computer.
The newest
trend in virus creation if the fast virus.
According to the British weekly, New Scientist,
Slammer, SoBig and MSBlaster were able to infect
tens of thousands of machines within hours of being
launched. The next generation of viruses will be
even faster. One called Flash Worm could infect an
entire network in 15 seconds, while the Warhol Worm
could spread worldwide in 15 minutes.
| Virus Information | Antivirus Software | What is a Worm? | Virus Hoaxes | Fast Viruses |
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