'Nitro' Cyberespionage Attack Targets Chemical, Defense Firms

Another wave of cyberespionage attacks -- this time targeting chemical and defense companies and traced to a hacker in China -- used an old-school attack method that harkens back to circa 1998.

The attacks, dubbed "Nitro" by Symantec researchers who yesterday released a white paper on the advanced persistent threat (APT)-style campaign, hit close to 50 companies, including 29 chemical firms and 19 firms mostly in the defense industry. Symantec says there are likely more victims out there as well. The attacks started in late July and ran through mid-September, but other companies outside of the chemical industry were targeted back in April.

The attack started with a phishing email sent to the targeted organizations, typically only a few messages, but in one case the attackers targeted 500 employees. The emails posed as security updates and meeting invitations, with one of the victim organization's actual business partners, and included an attachment that contained a self-extracting executable using the infamous PoisonIvy backdoor Trojan. The attackers went after administrator credentials and access to sensitive information at the targeted firm.

The method used by the attackers looks a lot like the Back Orifice attacks that plagued Windows systems in the late 1990s, points out Chris Wysopal, CTO at Veracode. "This was employees clicking on an .exe attachment, running as admin. It's like 1998 all over again," Wysopal says. The executable attachment slipping through an email gateway is exactly what Back Orifice did in 1998, he says.

One fairly innovative aspect of the attack was that it packaged PoisonIvy in an encrypted archive to help hide it from email gateways, says Chester Wisniewski, senior security adviser at Sophos Canada. "This 'nitro' attack has an interesting blend of malware techniques that does show some ingenuity," Wisniewski blogged today. "While the malware component of the attack was a recycled version of the common remote access Trojan (RAT) PoisonIvy, it was often packaged in an encrypted archive to evade email gateway detection.

Meanwhile, Symantec was able to trace the attacks to a virtual private server in the U.S., owned by a man who resides in the Hebei region of China who they say could possibly be the only or one of the attackers. The man, who Symantec nicknamed "Covert Grove," appears to have a connection to a "hacking for hire" service.

"When prompted regarding hacking skills, Covert Grove immediately provided a contact that would perform ‘hacking for hire’. Whether this contact is merely an alias or a different individual has not been determined. We are unable to determine if Covert Grove is the sole attacker or if he has a direct or only indirect role. Nor are we able to definitively determine if he is hacking these targets on behalf of another party or multiple parties," Symantec researchers Eric Chien and Gavin O’Gorman said in their report (PDF).

According to the report, 101 unique IP addresses representing 52 different ISPs or organizations in 20 countries "contacted a command and control server with traffic consistent with an infected machine." While Symantec did not name names, the researchers say the victims included Fortune 100 companies that conduct chemical compound R&D, "advanced materials," and that handle manufacturing infrastructure development for that industry, as well as companies that provide materials for military vehicles.

Like most APT-type attacks, the victim organizations have been hit by multiple attackers, not just those behind Nitro. "Attackers are sending malicious PDF and DOC files, which use exploits to drop variants of Backdoor.Sogu. This particular threat was also used by hackers to compromise a Korean social network site to steal records of 35 million users," the researchers wrote, and it's likely a separate attack conducted by a different group.

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