Virus Activity in the Internet Environment - High-Performance Web Databases: Design, Development, and Deployment - page 779

another, leveraging some network medium: e-mail, TCP/IP, etc. The worm is
more interested in infecting as many machines as possible on the network
and less interested in spreading many copies of itself on a single computer
(like a computer virus). The prototypical worm infects (or causes its code
to run on) a target system only once; after the initial infection, the worm
attempts to spread to other machines on the network.
The following is an example of the recent ExploreZip worm that uses an
e-mail message to spread:
Hi (recipient name)
I received your email and I shall send you a reply ASAP.
Till then, take a look at the attached zipped docs.
After a user clicks on the attachment, the worm searches hard drives C
through Z. It selects the Microsoft Word, Excel, and PowerPoint files, as
well as source code files, and destroys the data on those files. When exe-
cuted, the worm uses MAPI-enabled e-mail systems to automatically reply
to received e-mail messages.
VIRUS PROTECTION
Viruses can be controlled at the desktop, the file server, the gateway,
and on e-mail servers. Desktop and server anti-virus applications allow for
virus scan and detection on an ongoing and periodic basis, as well as each
time a file is downloaded or a computer is booted. More and more, com-
puter users have anti-virus software running full-time in the background,
scanning all files and diskettes the moment they are accessed. As macro
viruses proliferate, scanning e-mail attachments at the desktop is critical.
To protect networks, monitoring attachments at the e-mail gateway is just
as important.
Recommendations:
1. Avoid installing any unknown software (e.g., games, screen-savers,
etc.).
2. Be careful of software auto-installations from unknown/untrusted
Web sites.
3. Write-protect diskettes (ensure floppy is clean first).
4. Install and auto-scan all hard drives, floppy disks, files, and programs
with an anti-virus product at all times.
5. On a regular basis, update the signature files for the anti-virus
program (as viruses are created and identified, the fixes are included
in signature files).
6. Be aware of strange behavior on the computer system, such as the
keyboard making strange noises, characters dropping from docu-
ments, etc.