Giz Explains: How a Brainy Worm Might Jack the World's PCs on April 1S

It's lurking in millions of PCs around the world. It's incredibly sophisticated and resilient, with built-in p2p and digital code-signing technology. It revels in killing security software. On April 1, the Conficker worm will activate.

The scariest thing about the Conficker worm is that literally millions of infected Windows PCs could be linked together to do its bidding. The second scariest thing is that no one really knows what its creator is going to do with this virtual army on April 1, when it's scheduled to contact a server for instructions. It's so bad, Microsoft has a running $250,000 bounty for the author, dead or alive. (Well, they probably want him alive, but they hate his guts.)

The New York Times' John Markoff rounded up some of the more ingeniously evil possibilities in a compelling article, the most sinister being a "Dark Google," postulated by University of California at San Diego researcher Stefan Savage, that would let bad people scour zombie machines all around the world for data to sell to other bad people.

But let's back up a bit. Conficker—whose weird name is a combination of "configuration" and a slightly more polite word for f***er, according to Urban Dictionary—actually began life as a lowly, "not very successful" worm in November, says Vincent Weafer, VP at Symantec Security Response. Weafer told us it exploited a Microsoft remote server vulnerability that had already been announced and patched the previous month, so the only systems that were vulnerable were the ones that weren't up to date.

The B release, pushed in December, on the other hand, was "wildly successful," says Weafer, infecting millions of unpatched computers because it's an aggressive little bastard—the first worm in years on a scale like Blaster. It has built-in p2p capabilities, and brute forces its way into open shared folders or printers, so it can crawl an office network quickly. It also piggybacks onto USB flash and hard drives. On top of all that, it's designed to be incredibly resilient, killing security software, disabling Windows Update, and digging down deep.

The C release came out this past month. It doesn't go after new machines—it's actually a payload for computers already infected with B. It transformed Conficker from a sneezing pandemic into a seriously nasty plague. With C, its p2p powers are extended further, with digital code-signing, so it only accepts trusted code updates from itself. That means security experts can't simply inject code to neutralize it. The patch also made Conficker better at killing security software. And it expanded the scope of the domains it tries to contact for instructions from 250 to 50,000, completely neutralizing security experts' previous tactic of seizing the domains. There's effectively no way to the cut the head off of this demon snake. The stage is set: On April 1, Conficker will reach out for the millions-strong zombienet's next set of instructions.

So what will happen? Well, no one knows for sure. Conficker's creator can do whatever he wants with his army. Launch massive denial-of-service attacks, setup the "Dark Google" syndicate, target millions of new machines, or generate a tidal wave of spam that'll crash against servers all over the world.

Most likely though, Weafer told us, Conficker's creator is motivated by money—they'll rent it out. And if Conficker's used as a massive doomsday tool, they'll "quickly lose the ability to make money" with it. A low key operation harnessing the power of computers that are mainly located in developing nations may not have a big impact, though it would certainly set a terrible precedent: Whatever Conficker's results, they will lead others to develop this idea in frightening new directions.

Conficker's innovative approach that utilizes p2p, code-signing and a distributed domain setup will very possibly serve as inspiration to other malware writers, who Weafer said "you can bet" are watching Conficker's success very closely, just as Conficker's creators have clearly learned from past malware. It's like evil open source.

That doesn't mean April 1 will be a "digital Pearl Harbor." If your machine is patched and up to date, the Microsoft Report's Ed Bott tells us, you'll probably be totally fine. And yes, you can get rid of it if you happen to be infected. There is an outside chance Conficker could turn into a massive parallel computer that borders on self-aware, come April 1, but more than likely, the day will come and go without you noticing anything weird, just some extra spam in your box for some V@ltr3xxx.

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