Targeted attacks are evolving faster than victims can detect them, and it's not just about cyberespionage anymore, either: Financially driven cybercriminals are also using advanced persistent threat (APT) methods for longer staying power in order to increase their spoils.

The APT attacker traditionally has been associated with Chinese cyberspies, but the types of attacks waged to steal intellectual property are increasingly blurring as new players and regions enter the landscape. Among the newcomers to this attack model are traditional, financially motivated cybercriminals and cyberspy attackers from Russia.

Recent research from Mandiant, HBGary, and Trustwave SpiderLabs demonstrates how the advanced targeted attack is becoming increasingly difficult to pin down.

While most organizations rely on security tools that detect malware, that's only part of the advanced attack equation, security experts say. "There are so many [of these] attacks going on now," says Greg Hoglund, CEO of HBGary, who says his firm is tracking around 18 different APT groups. "You're not looking for just malware -- it's behavior you're looking for. They leave behind forensic evidence, [namely] things your employees don't do."

Mandiant, in its new annual M-Trends report on advanced threats, also says finding the malware from an APT or advanced attack is only the tip of the iceberg. According to data gathered by Mandiant in its investigations for clients, malware-infected machines represent only 54 percent of the systems compromised in the attack. In all cases, the attackers employed stolen, legitimate user credentials to move about the network.

And these attackers aren't always coming up with their own zero-day attacks, either. In 77 percent of the cases Mandiant investigated, the attackers had used publicly available malware.

Mandiant and other security firms are also finding that the persistent, under-the-radar technique traditionally employed by Chinese hackers for stealing intellectual property is now also being adopted by cybercriminals out for financial gain rather than IP.

Researchers at Trustwave SpiderLabs have noticed that trend, as well. Nicholas Percoco, senior vice president and head of Trustwave SpiderLabs, recently noted this shift when discussing the firm's latest Global Security Report for 2011. "Attackers are becoming more sophisticated and without being detected," he said in an interview last month with Dark Reading. "Smash-and-grab attacks are few and far between. It's all about persistency: You hear a lot about espionage and APT attacks. But there's no reason why organized crime groups after financial information would not want to be using the same techniques [APTs] are."

Mandiant's report echoed the same trend. While these financially motivated attackers have often used the "smash-and-grab" approach with simple tools, that's changing, according to Mandiant. "Organized crime groups are adopting persistence mechanisms previously used by the advanced persistent threat. The long-term access these techniques enable allows the attacker to steal more data over a longer period of time to gain access to more lucrative data, and to ensure their data is a fresh as possible," according to Mandiant.

Among their weapons of choice for staying put longer and under the radar that Mandiant has seen are custom backdoors, publicly available backdoors, Web shells, Metasploit Meterpreter, and remote access utility tools.

But it's the attacker's lateral movement within the targeted organization that can go unnoticed and incur the most damage. "A company could have 50,000 nodes, and you may find 100 machines exhibiting [certain behaviors]," some of which appear normal, but then another raises suspicion, such as a user opening up an interprocess communication port, Hoglund says.

Mandiant says that only 6 percent of victim organizations they helped discovered the attacks on their own. Most found out from external sources, including law enforcement. And these attacks typically go on for more than a year before they are found out.

While most of these attacks have ties to China, Russia also increasingly is showing up on the radar screen, as well. Both Mandiant and HBGary's Hoglund report spotting such activity out of Russia. "The two biggest threats to the U.S. are Russia and China," Hoglund says. "We've caught false flags before ... Russian [attackers] trying to insert Chinese language in there" to appear to be Chinese attackers, he says.

The trick is spotting and analyzing the behaviors and not just the malware, security experts say. And don't assume you're immune, because these attacks are spreading across various industry sectors. According to Mandiant's report, 23 percent of the attacks are hitting the communications industry; 18 percent, aerospace and defense; 14 percent, computer hardware and software; 10 percent, electronics; 10 percent energy and oil and gas; and 25 percent in other various industries.

"I'm meeting more CSO's saying, 'All I care about is APT,'" says Bruce Schneier, CTO of BT Counterpane. "It's now all about agile security and detection."

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