Concerned with the amount of U.S. intellectual property being stolen from corporate networks, a groups of security professionals sat down and compared notes on the various groups they tracked. They came up with an approximate tally of attackers targeting the intellectual property of U.S. and multinational companies: an even dozen, and all thought to be Chinese.

High-tech firms, oil companies, and defense contractors have all fallen prey to the 12 teams out to steal trade secrets and sensitive or classified information. While attempting to identify and count the groups behind the attacks might seem like an academic exercise, it's not, says Jon Ramsey, executive director of Dell Secureworks' Counter Threat Unit.

"In the general scheme of things, knowing who your enemy is is enlightening," he says.

One group, for example, is called the Comment Crew by Dell Secureworks because of its signature tactic of embedding command-and-control information in the comments of Web pages. "Understanding that, if you wanted to deal with the major attack from this one group, you can strip all comments out of the HTML pages as they come into your Web proxy," Ramsey says. "That is a pretty effective technique to deal with this one group."

Moreover, knowing whether an attacker is part of the advanced persistent threat (APT) -- the term coined by the defense industry for attackers that don't go away -- can determine whether a company calls in help. When a company suspects that a persistent attacker has set up shop inside their network, kicking them back out again is not easy, Richard Bejtlich, chief security officer for security consulting firm Mandiant, said in a recent interview.

Various attributes can be used to classify attackers into groups, including their tools and techniques, the characteristics of their infrastructure, and their targets. Mandiant, for example, keeps dossiers on the 12 groups it tracks, and when called in by a client, compares and gathers network intelligence with what it knows about the usual suspects. The company can analyze an incident under investigation and match it to various groups' modes of operation, including their tools, passwords, encryption used, command-and-control infrastructure, and targets.

"If we find that enough characteristics match, then we say, 'OK, it's likely that you have this [APT] problem,'" he says.

Not everyone believes the problem of advanced attackers can be put at the collective feet of 12 groups. Hundreds of hacking groups on the Internet have the capability to steal intellectual property, says Greg Hoglund, CEO of security firm HBGary.

"I have [information on] two groups up on my wall right now that are both oil industry attackers, and they are not in the dozen groups," he says.

[Traditional security information event management (SIEM) systems typically don't detect a relentless targeted attack designed to avoid raising any red flags, but APT-type attacks are forcing SIEM to evolve. See APT Shaping SIEM.]

In addition, groups in other countries, such as Russia and Iran, are active as well. Companies in specific industries or operating in certain countries might have to worry about attack emanating from other nations, such as Iran's apparent focus on compromising certificate authorities to gain access to dissidents' communications.

Yet because the majority of attacks come from the 12 Chinese groups, companies targeted by advanced attacks should mostly worry about the Chinese groups, says Bejtlich.

"The amount of activity you get from all the other [groups] who are out there doing this stuff is so swamped by what's coming out of China," he says.

It's an assessment that others agree wit,h as well.

"I think there is a big cliff between No. 1 and No. 2, whoever No. 2 might be," says Dell Secureworks' Ramsey.

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