Five global energy and oil firms have been the target of "coordinated covert and targeted cyberattacks" by hackers based in China, according to net security firm McAfee.
The five unnamed petrochemical giants are confirmed victims of the so-called Night Dragon attacks, which began before November 2009 and remain ongoing.
Evidence suggests a further seven firms were hit by a series of attacks that used a combination of social engineering, spear-phishing, Windows exploits, Active Directory compromises and the use of Trojans.
Hackers used a combination of these attacks to target sensitive data including "proprietary operations and project-financing information on oil and gas field bids and operations".
The attacks, confirmed as ongoing for at least two years and possibly dating from at least four years ago, probably originated from China, according to various strands of circumstantial evidence.
"The tools, techniques, and network activities used in these attacks originate primarily in China," explained McAfee CTO George Kurtz, in a blog post.
"These tools are widely available on the Chinese Web forums and tend to be used extensively by Chinese hacker groups. McAfee has determined identifying features to assist companies with detection and investigation."
McAfee has published a white paper on the attacks, which provides more information on attack mitigation and further background on the alleged assault.
The latest attacks follow the same pattern, and use broadly the same malware along with social engineering trickery, as the Operation Aurora attacks against Google and other hi-tech firms last year. McAfee said that the two operations used different attack profiles and malicious tools.
It's possible that the real perpetrators of the attack are using Chinese tools and compromised Chinese PCs to launch the latest assault, so as to point the finger of blame towards China. But as things stand the Chinese state (which has extensive cyberespionage capabilities) remains the prime suspect.
Last year the Christian Science Monitor reported on Aurora-style targeted attacks against Marathon Oil, ConocoPhillips and ExxonMobil dating. Data harvested via the attacks included information on new energy discoveries, just like the sort of data targeted by Night Dragon. Each of the targeted firms only become aware of the assault following notification by the FBI. ®