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Browser Hijacking
Recently we did a tech tip on spyware, those sneaky programs
that hide on your system and collect information about your
computer usage, which is then reported to someone over the
Internet. However you might feel about this invasion of
your privacy, spyware does have the advantage that it runs
in the background and usually doesnt interfere with
your use of the computer, other than maybe slowing it down.
Spyware has a close cousin called a browser hijacker that
is a lot harder to ignore, because it takes you somewhere
on the Internet that you didnt plan to go. That somewhere
is usually either a porn site or some wannabe search engine.
You might wonder what advantage a website would see from
dragging people in who didnt want to be there and
who would be annoyed by it, at the very least. There seems
to be two motivations at work here. One viewpoint, prevalent
with porn-site webmasters, is that because the cost is minimal
it is perfectly OK to attract 1000 annoyed visitors, or
100,000, as long as one of them likes what they see and
takes out the credit card. The other motivation applies
to sites that charge for advertising based on the number
of visitors. In the short term, the fee is the same whether
the visitors are willing or not.
In its simplest form, the hijacking program will just substitute
its choice of URL into your browsers address bar.
A more efficient variant replaces your default home page
and search page, so that you are hijacked immediately whenever
the browser opens, and again when you try to do a search.
Some versions are quite specific about when they substitute
a URL. For instance, they may look for Google, Yahoo and
other search engines, and then redirect you to another search
portal. Some will redirect the browser whenever a non-existent
URL is entered, because of a misspelling or broken link.
Instead of seeing the usual prompt that says, The
page could not be found, you see the hijackers
web site. And some porn sites will only hijack when you
attempt to access one of their competitors.
Many versions will also add bookmarks to your desktop and/or
your Favorites list, sometimes deleting the original contents
of the Favorites file. A fair number of them have a hidden
file that will recreate the program at bootup, so that even
if you manage to kill the hijacker, it keeps coming back
like something out of a Steven King story.
In spite of all the variations, these bits of malware (malicious
software) seem to originate from only a couple of sources,
and are then modified (or copied outright with only URL
changes) by one unscrupulous webmaster after another. The
first hijacker to become widespread was associated with
the site lop.com (and no, we dont recommend that you
go there to check it out). More recently, one called CoolWebSearch
has spawned over 80 known variations. Both of these source
programs were designed for Internet Explorer, simply because
it is the most common browser, but some of the variants
also affect Netscape and Mozilla.
OK, enough of the bad news. What can we do about it? Sometimes
all that is needed is to re-enter the URL you wanted in
the first place. And if the default home page has been replaced,
right-click on the Internet Explorer icon and select Properties
from the pop-up menu. On the General tab you can restore
the default home page. While you are there, delete the cookies
and Temporary Internet Files, because some of the less sophisticated
hijackers use these. Others will use the Windows\Temp folder,
whose contents should also be deleted. If these simple measures
fail or the program keeps coming back, its time to
bring out the big guns.
If the hijacker variant infecting your computer has been
around for a while, it may be detected by your antivirus
software. Anti-spyware programs such as Spybot and Ad-Aware
are also good at spotting the older ones, but the more recent
variants may slip through the net. A better option is one
of the programs designed specifically for handling hijackers.
Two of the most popular are shareware programs created by
a Dutch programmer who goes by the name of Merijn. The basic
one is Hijack This, which looks for a wide variety of hijackers.
It provides an assortment of tools and a log file that is
very useful for ferreting out hijackers that hide in system
folders and such. It is a little complicated in practice,
but you can find several good tutorials on the web to help
in interpreting the log file and determining the correct
course of action to clean out the invader.
A second program called CWShredder was created specifically
for the many variants of CoolWebSearch, which has been mutating
too fast for Hijack This to keep up. CWShredder will not
only spot most versions of the bug, it also gives you a
simple one-click fix-it option. Both of these
programs are kept fairly up-to-date, and you can find either
of them at: http://www.merijn.org/downloads.html. Although
the downloads are free, there is a PayPal button on the
site that allows you to make a donation. If you find these
programs useful, please consider the donation. I dont
know about you, but I would like Merijn to continue fighting
this battle for us as long as possible.
Disclaimer - The Micro 2000 Tech Tip is a free service
providing information only. While we use reasonable care
to see that this information is correct, we do not guarantee
it for accuracy, completeness or fitness for a particular
purpose. Micro 2000, Inc. shall not be liable for damages
of any kind in connection with the use or misuse of this
information.
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