A Word on Security
By David
Fishman
Recently The Tisser virus was found on my
computer at work. The computer is a brand new laptop with virus
software that is run on a daily schedule. Yet this computer was
infected so effectively the hard drive needed to be replaced. I
noticed the problem with my computer when my browser homepage
was changed without my choosing. This practice is called browser
hijacking and it is the latest plague to hit the Internet. It
most commonly shows up as ad banners from dubious companies that
suddenly appear during every visit online, even after the
computer is restarted.
https://www.lynxtrack.com/signup.php
The problem is particularly
common with Microsoft's Internet Explorer Web browser, which
comes preinstalled on almost all Windows PCs.
Users of other browsers or
operating systems like the Mac OS, FireFox, and Linux are much
less frequently affected.
The most common form of
browser hijacking involves switching a user's designated home
page to some advertising site, but this is unfortunately not the
only form.
The most aggressive of these
programs change all of the Internet addresses stored in the
browser and even change manually entered addresses to bring the
user back to ad pages - in many cases pornographic in nature.
The user is then unable to call up other pages at all.
Many Trojan programmers earn
money by luring Internet users to click on the Web pages, and in
these cases there are no real damages to the owner of the
hijacked browser. In many other cases, however, the criminals
are fishing for a much more lucrative source of income.
Dialers, little programs that
dial toll numbers using the computer's modem or ISDN connection,
will attempt to make their way onto the computer using the
hijacked browser.
One IT director advised,
“Once you determine that the browser has been hijacked, you
shouldn't click anything further on the page that has been
called up," warns Frank Feldman from the BSI in Tel Aviv.
In order to avoid falling
into the hands of browser hijackers, keeping the computer system
as current as possible and always downloading the latest
software improvements, known as patches, from Microsoft's
Internet site.
This function can be
activated using the "Windows Update" button on the Windows Start
menu. It's also advisable to download a second browser like
Firefox or Opera to act as a reserve.
Standard security measures
against viruses should also be observed. This includes a current
virus scanner, despite the knowledge that Trojans frequently
make it past these security checkpoints. Email attachments from
unknown senders should be deleted immediately, unopened.
The most dangerous phase is
the period after a security hole is found in the Windows system
but before the software maker can prepare a corresponding patch
to close the hole again.
Those who program browser
hijackers often wait for this phase to try and infect a
computer's Windows registry, a type of database that stores all
important settings for hardware and software that the operating
system needs. Trying to repair this complicated system by
removing entries made by Trojans is possible on one's own, but
not advisable.
Most experts I spoke with do
not recommend having an individual user fix the system without
some type of professional virus software to help. The experts
instead recommend using special programs designed to remove
these entries, and the bad software itself. Most of the Virus
software is easy to use and can be downloaded for free on a
trial basis or free forever depending on the brand chosen.
David Fishman
dfishman@wrpmedia.com
