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CoolWebSearch is winning Trojan war
Programmer bows out
Merijn Bellekom has abandoned developing software that removes one of the nastiest browser hijackers on the planet: CoolWebSearch, a trojan that converts your PC into a source of revenue for fly-by-night porn sites not capable of generating legitimate Web traffic.
The trojan installs dozens of bookmarks to foul porn sites on your desktop; it also adds a toolbar to Internet Explorer and changes your home page without asking. And it significantly slows down the performance of your PC, and introduces some modifications which cause Windows to freeze, crash or randomly reboot.
It takes a brave Dutch student, Merijn Bellekom, to remove the hijacker effectively; but CWS seems to be winning, leaving users at risk.
Bellekom has just released the latest version of his CWShredder (1.59), the only antidote to the trojan, but warns that his app won't be updated again: "I have a few bugs to fix, but after that there's not much left to do. I simply do not have the tools to remove the latest variants. They are too aggressive or too complicated to allow for automated removal."
He has tracked CWS and its modifications ever since it first appeared last summer, claiming that it is "the most complex, invisible and devious hijacker" ever programmed. He is not joking: We run afoul of CWS not too long ago and the only way to remove the sucker was to replace the entire Windows Registry with a previous version. Even MSIE 6 Service Pack 2 (beta) couldn't provide any protection.
The first modifications weren't even identified as such, according to Bellekom. Users began to report significant slowdowns when they typed messages into text boxes. Merijn believes CoolWebSearch is part of a new strain of trojans that install through the ByteVerify exploit in the MS Java Virtual Machine.
Fighting CoolWebSearch has become a daunting task. The criminals behind it often engage in Distributed Denial of Service (DDoS) attacks against sites that host CWShredder. Some variants try to cripple CWShredder and other spyware removal tools. New versions of CWS are released almost every few weeks. Bellekom's chronicle of variants pretty much reads like a horror story. Merijn calls the latest variants "a living hell".
Some have already volunteered to update CWShredder, but rather than playing a never-ending cat-and-mouse game, why not hunt for the people behind it? Sites such as Webhelper4u already provide a lot of evidence of their whereabouts.
The trojan often redirects users to sites affiliated with CoolWebSearch, a Russian pay-per-click search engine where companies can bid for keywords. The site accumulated over 1000 affiliates since last year, all with their own site. CWS itself denies any involvement with the trojan: "We are buying surfers' searches from webmasters all over the world. Maybe some webmasters, who are sending visitor traffic to us, are challenging your system's security," the company says.
Perhaps. But only if there is money involved. Do largely unknown Russian search sites or their affiliates earn that much money? We doubt it, not without the help of their western counterparts, anyway. Which may be the key to the solution: follow the money trail and you may get some answers. ®