Rootkits are becoming more prevalent and difficult to detect, and security vendor McAfee says the blame falls squarely on the open source community.
In its "Rootkits" report being published today, McAfee says the number of rootkits it has collected as malware samples has jumped ninefold this quarter compared with the same quarter a year ago. Almost all the rootkits McAfee has identified are intended to hide other code (such as spyware or bots) or conceal processes running in Windows systems.
"The predominant reason for the growth in use of stealthy code is because of sites like Rootkit.com," says Stuart McClure, senior vice president of global threats at McAfee
Rootkit.com's 41,533 members do post rootkit source code anonymously, then discuss and share the open source code. But it's naïve to say the Web site exists for malicious purposes, contends Greg Hoglund, CEO of security firm HBGary and operator of Rootkit.
"It's there to educate people," says Hoglund, who's also the co-author with James Butler of the book Rootkits: Subverting the Windows Kernel. "The site is devoted to the discussion of rootkits. It's a great resource for anti-virus companies and others. Without it, they'd be far behind in their understanding of rootkits."
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No one with a profoundly malicious intent would post his rootkit on the site, because it would be publicly analyzed for detection purposes, Hoglund says. He concedes, however, that out of the tens of thousands of Rootkit participants, there are bound to be those whose intent is to exploit rather than learn.
Anti-virus vendor Trend Micro says the Rootkit Web site cuts both ways.
"We need those open source people," says David Perry, global director of education at Trend Micro. "They uncover things. It's a laboratory of computer science. They demand the intellectual right to discuss this."
That said, Perry notes there are a lot of hacker wannabes who would be drawn to using the Rootkit site "as one-stop shopping for them to pick up the tools."
Designing a rootkit is a complex programming process. Hoglund says there are probably no more than 20 or 30 main types today, along with a wide number of variants.
Detecting rootkits has become a software research frontier, but eradicating them and what they hide is proving even more difficult.
"I don't think it's fair to say Root kit.com is abetting the spread of rootkits. They were present before Rootkit.com," says co-author Butler, CTO at Komoku. Komoku is getting ready to release a rootkit-detector code-named Gamma.
Butler says Rootkit.com has made it easier to use such software. "Technology being deployed today is now more sophisticated than it was two years ago. It's very advanced," he says.
"Eradication is extremely difficult to do in 100% of the cases, while restoring a system and keeping it stable," Butler says. Some rootkits that can get into the [basic input/output system] might make it advisable "to throw the computer away" if you want to be sure you got rid of the rootkit, he says.
A Microsoft official offered similar advice two weeks ago at the InfoSec Conference in Orlando.
Rootkits with names including HackerDefender, AFXRootkit, PWS-Progent and FURootkit are cited by McAfee as among the most prevalent today.
The trend is toward embedding stealth technologies with varying forms of spyware and malware, such as Backdoor-CEB, AdClicker-BA, W32/Feebs, Backdoor-CTV, Qoolaid, PWS-LDPinch, Opanki.worm, and W32/Sdbot.worm.
This makes it harder to detect and eradicate spyware, adware and other unwanted code, McAfee's McClure says.
The growing fear in the security world is that it won't be long before someone creates a worm that can scan networks for vulnerabilities and then effectively deliver a malicious payload - such as something that can wipe out files, change data or spy on organizations - that can be kept hidden by a well-made rootkit.
"It's quite possible, once you've got a piece of code on someone's computer," Perry says.