Anti-Virus Software Frequently Asked Questions About Viruses Virus questions are some of the most common responses to our newsletter. Below are some answers to the most common.

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This original version of this FAQ appeared in the Evron Solutions Newsletter.

Learn More About: Viruses and Computer Infections

Basics: What is a virus? | How does a virus get loaded on my system? | Can I get a virus just from reading my email? | Can my email be "wiretapped" - tracked and read by others? | What are some ways to deal with the threat of viruses? | How do viruses spread? | What does it mean if a Virus is "In the Wild?"

Hoaxes: What's a Virus Hoax - Are they Dangerous? | What's an example of a hoax? | How can I tell the difference between a Hoax Virus and a real one?

Effects: What is a Denial of Service (DOS) Attack? | How should I set up my Email software?

What is a virus? top

A virus is a computer program, or a piece of code. However, unlike other 
programs, a virus is hidden, and loads itself onto your system without 
your knowledge. Viruses are often written with malicious intent and therefore 
can do a number of damaging or simply annoying things to your system. 
For this reason they are often referred to as "Malware" (for MALicious 
softWARE).

The other thing that makes viruses different from other programs is that 
they are designed to spread - sometimes within a computer, sometimes between 
them. 

How does a virus get loaded on my system?  top

Viruses hide by attaching themselves to a normal file or program. When 
that file is opened, the virus program activates and loads itself onto 
the user's system. 

In many cases, a user will accidentally cause a virus to load by opening 
an infected file such as a Word document or piece of downloaded software.

A virus may also enter your system if you use an infected floppy disk to 
boot up your computer. The virus masquerades as the computer's start-up 
program and is run as the computers boots up. This is called a "Boot Sector 
Virus" and has become less common in recent years.

A virus may also use JavaScript or ActiveX to load itself onto your system 
when you open an email. This is discussed further below.
(Click here for information about disabling JavaScript and ActiveX in email)

Can I get a virus just from reading my email? top

Yes and no. In general, you should not be able to get a virus from reading 
email, because emails are simply text and a virus requires that a program 
be launched. However, in order to increase their functionality, some email 
programs - including Microsoft Outlook, Outlook Express and Netscape Messenger 
- may allow senders to use JavaScript and Active X applets. 

These can be programmed to activate as soon as an email is opened, thus 
allowing a virus to spread. For ways to adjust your programs to avoid 
this, see Tech Tips, below.

Can my email be "wiretapped" - tracked and read by others? top

Most people believed that it could not. However, it has been discovered 
that this could occur in those email programs that allow JavaScript. This 
includes those discussed above, and others. A programmer can implant in 
the email a script that causes replies and forwards to automatically be 
copied to a third party mailbox. To avoid this, the JavaScript functionality 
must be disabled.
(Click here for information about disabling JavaScript and ActiveX in email)

What are some ways to deal with the threat of viruses?  top

PRACTICE SAFE COMPUTING:
- Back up your files regularly. A virus only destroys data. As long as 
you have another copy of this data you can always get it back. 
- Scan all newly obtained disks, programs, and files.
- Ensure you have an emergency, write protected boot disk to start your 
computer, in case the usual start up program is infected.

BE WARY OF EMAIL ATTACHMENTS: 
- Delete any file attachments or programs sent from an unknown source.
- Save attachments to disk before opening them. Most of the Anti Virus 
programs check for Viruses when files are written to Disk. Opening the 
attachments without saving can pass thru some Anti Virus programs undetected.

PROTECT YOURSELF WITH SOFTWARE:
- Use good Anti-virus software, keep it updated and obtain necessary add-on 
components to protect your specific Email server. 
- Ensure that your email and security software is properly configured and 
contains the most recent patches. 
- Any computer that has a constant Internet connection should be protected 
from outside attack with a Firewall. This includes home computers and 
company LANs.

How do viruses spread?  top

General Viruses: General viruses spread by copying themselves from file 
to file WITHIN a computer. These are only spread between computers through 
human activity - through sharing of infected disks, files and programs. 
One of the first famous general viruses was MICHELANGELO Virus.

Worms: Worms are designed to copy themselves BETWEEN computers. They either 
move through security holes in network or file transfer software or through 
email. For example, the recent "Anna Kournikova", "Melissa" and "I love 
you" worms caused MS Outlook to automatically send emails containing the 
infected program to a user's entire contact list without their knowledge.

What does it mean if a Virus is "In the Wild?" top

A Virus that has been detected on more than one computer is considered 
"In the Wild" and is an active threat. This is in contrast with a "Zoo 
Virus" which is only on one computer and is being used for research.

What's a Virus Hoax - Are they Dangerous? top

As a result of the widespread fear of virus infection, many hoaxes have 
been created which warn of a deadly virus and demand that you forward the 
message to your entire address books. In general these are benign, but 
many people see them as a form of virus themselves because of the time 
it takes for every recipient to read and forward the warning along.

What's an example of a hoax? top

One example is the "Virtual Card for You" hoax.

> Do Not Open ANY Emails that Begin with: "A Virtual Card for You" OR "An
> Internet Flower For You"
> 
> The full details are included below. 
> 
> A new virus has just been discovered that has been classified by Microsoft
> and by McAfee as the most destructive ever! This virus was discovered
> yesterday afternoon by McAfee and no vaccine has yet been developed.
> SEND THIS TO EVERYONE ON YOUR CONTACT LIST!!!!

How can I tell the difference between a Hoax Virus and a real one?  top

There is no way to guarantee that a certain virus warning genuine or not, 
but there are a number of characteristics which are common to hoaxes:

- Damage is always extreme and there is never a cure
- Tone of the letter is extremely urgent
- LOTS of CAPITAL LETTERS and EXCLAMATION POINTS!!!!!
- Often warns that damage will occur just from opening your email 
(While this is theoretically possible it is unlikely. For most viruses 
to activate you have to open an attachment.)
- Demands that you forward the email to everyone on your contact list
- Doesn't provide a proper link for more information

When judging the credibility of a Virus warning consider who's sending 
it to you, and always look for a link to an AUTHORITATIVE information page 
about the virus. For more information see the home page of your anti-virus 
software company. 

What is a Denial of Service (DOS) Attack? top

Web Bite: The site is flooded with a massive amount of connections which overloads the server and causes the site to go down. The attack is typically carried out by many "zombie" computers that are under the control of a computer virus.

Network: In a similar way, a company's network is flooded with a massive number of emails or other communications. By giving the server more traffic than it can handle, the loses access to internet or email.

How should I set up my Email software? top

One aspect of safe computing is for your Outlook to be set up properly. Below are a couple of good ideas:

Disable Your Email Preview Pane: Some viruses will launch themselves even if you only open them up in thepreview pane. To close this pane in Outlook and Outlook Express go to the View menu. Depending on which program and version you are using, the Preview Pane option may be in the view menu, or under View -> Layout.

Disable "File Download" in Web Browser: In the case of some web-site based viruses (such as Nimda), users visiting compromised Web servers will be prompted to download an .eml (Outlook Express) email file,
which contains the worm as an attachment. Users can disable 'File Download'
in their internet security zones to prevent compromise. Here's How:

In Internet Explorer
Go To: Tools -> Internet Options -> Security tab
Click: Custom Level -> move down the list until you reach "File Download".

There will be three options: Enable, Disable and Prompt.
Choose Disable,
Click OK and save your changes

Install Recent Software Patches: Companies like Microsoft regularly release security patches for their software, especially email software like Outlook. It is important to ensure that your software is always up to date.

For more information on proper software setting and updating contact Evron at 905-477-0444 or email info@evron.com.