For internet users seeking to avoid exposure to spyware and intrusive ads, the prevailing wisdom among net security experts has long been that a good first step is to switch from Microsoft's Internet Explorer to an alternate browser.
But now that millions have taken the advice and changed to browsers like Mozilla Firefox, more spyware and adware writers are also making the switch.
As the number of people opting not to use IE grows, makers of filtering software say users of leading alternate browsers can expect to see more intrusive ads and spyware applications headed their way.
"There's still a lot more spyware that gets in through the holes in Internet Explorer than through the holes in Mozilla, but it's changing," said Anthony Arrott, director of threat research for InterMute, a maker of software that blocks spyware and pop-up ads.
As of today, spyware writers have not successfully targeted Firefox users on a large scale. However, Arrott says that spyware writers are more attracted to Mozilla today simply because it has more users. A few years ago, when Internet Explorer dominated the browser arena to a greater degree, there wasn't much reason for authors of malicious applications to target its rivals. Now that Mozilla has critical mass, however, it's become worth their while.
"The reason there is so much spyware in IE and not on these alternate browsers is not because IE has so many more inherent security problems but because IE has so many more users," Arrott said. As other browsers become more popular, he added, spyware users will go after them too.
The upshot of spyware writers' newfound attraction to Mozilla, Arrott predicts, will be that in the next six months or so computer security guides will stop recommending that people switch from IE to halt intrusions.
It's not just spyware that users of alternate browsers are complaining about. Much-reviled pop-up and pop-under ads are also making it past blocking software, a trend that Matina Fresenius, chairman and CEO of ad-blocking software developer Panicware, attributed to the fact that most older programs were made with IE in mind.
"I'm not sure if it's specifically that advertisers are finding ways to sneak by ad blockers in alternate browsers. I think it's just that most ad blockers don't support the alternate browsers," said Fresenius, whose company launched a pop-up blocker last week that is designed to work with both IE and alternate browsers like Mozilla, Opera and Netscape.
Mac users are also complaining about a rise in intrusive advertising. In the past few months in particular, Mac users have reported a dramatically higher incidence of unwanted pop-up and pop-under ads, said Ben Wilson, senior editor of the Mac site MacFixIt.
Typically, Wilson said, Mac users are subjected to fewer unwanted pop-up and pop-under ads than PC users. He attributes this tendency to security features in Mac OS X's architecture and to its smaller market share.
Still, Wilson said, a handful of ad delivery firms openly boast about their ability to subvert traditional blocking systems, and Mac users are feeling the effects of some aggressive advertiser tactics.
One advertiser site, Popuptraffic.com, states on its homepage that "due to the proliferation of pop-up blockers, we have altered our popup code so that if a blocker is detected, a layer ad will be delivered." Other firms, Wilson said, are using a technique in which advertisements load in the background when a person is viewing a web page, then appear immediately when he or she attempts to visit another URL. Others will force another pop-up on the user if the first is closed "too quickly."
For the most part, however, Wilson says Mac users can keep pop-ups and pop-unders from becoming a nuisance by installing blocking tools such as PithHelmet.
While pop-ups and pop-unders may seem to be getting more troublesome to certain users, broad internet traffic data indicates that their numbers are actually declining. According to internet measurement firm Nielsen/NetRatings, advertisers are using fewer pop-up and pop-under ads, largely because so many people have installed software to block them. In January, NetRatings found that advertisers recorded 918 million impressions of pop-up ads, down from 2.2 billion in the same period last year.
At the same time, other forms of online advertising often criticized as intrusive -- screeching animations and floating ads that superimpose themselves over a page -- are on the rise.
