There's a new phrase for an old threat, "drive-by downloads." There are several companies, which, following in the footsteps of the many virus writers which preceded them, hijack the browser, replacing the home page, popping up banner ads, and secretly installing more software on the unsuspecting user's computer. They do so under the guise of providing you with an Internet Explorer toolbar.
Toolbars are those rows of icons across the top of a program. Toolbars provide quick access to oft-used commands such as printing. In your toolbar right now, you probably have "back" and "forward" buttons. Microsoft's Internet Explorer Web browser offers developers the ability to provide customized toolbars such as the Google Toolbar, which provides quick access to Google's search features. Other toolbars display stock quotes or current news.
A company called Xupiter also provides an Internet Explorer toolbar. If your security settings are low, [ed. Thick sarcasm] they are even so kind as to automatically install the toolbar for you. If not, then you have to agree to allow them to install the toolbar. Once installed, Xupiter changes the victim's home page and redirects all searches to the Xupiter site.
Xupiter victims are inundated with pop-up ads, including ads for casinos. They also experience odd browser behavior such as form fields self-populating with random text. Like most poorly written software, the Xupiter uninstall does not work. Of course, as is true with viruses, the user was never meant to uninstall the toolbar.
The only prevention is to make sure your Internet Explorer security settings are set appropriately. For most people, the default settings are appropriate. We have provided instructions on how to reset your Internet Explorer security settings to their default values in the Frequently Asked Questions portion of our site.
It is worth noting that, in the infamous anti-trust case against Microsoft, Microsoft argued that Internet Explorer could not be removed from Windows, that it was tied to the operating system and not just a program that ran on top of it. Others testified against this, arguing that, though not easily accomplished, Internet Explorer could be "uninstalled" from Windows.
Regardless of which you choose to believe, Internet Explorer is undeniably integrated into Windows at a lower level than just about any other program. As such, installing any program which makes changes to Internet Explorer can be dangerous. This is especially true of applications which offer to "customize" Internet Explorer, speed up your Web browsing experience, or help improve your searches. Such seemingly benign programs may render your entire system unusable.
If this isn't reason enough to use caution when installing Internet Explorer toolbars and plug-ins, then consider the security ramifications. Many programs use Internet Explorer to accomplish their tasks. This is even true of viruses, many of which exploit vulnerabilities in Internet Explorer to deliver their payload. So, consider your security and privacy before installing an application which integrates into Internet Explorer and may change your security settings to something less restrictive than their default values.