Tainted digital versions of the report from cyber forensics firm Mandiant infect PCs with computer viruses that allow hackers to gain remote control of computers after users attempt to read those documents, according to security researchers.
Anti-virus software maker Symantec Corp said on its blog that some of those tainted documents were attached to Japanese-language emails purporting to be from someone recommending the report.
Security engineer Brandon Dixon said on his blog that he had identified a similar document on the Internet, which appeared to have originated in India.
"It was only a matter of time," Mandiant said on its blog, adding that its own network had not been compromised. "Reports downloaded, previously and currently from our website, do not contain exploits."
The report, which is available from Mandiant at http://intelreport.mandiant.com/ charges that a secretive Chinese military unit is behind a series of hacking attacks. It prompted a strong denial from Beijing and accusations that China was in fact the victim of U.S. hacking.
(Reporting By Jim Finkle; editing by Andrew Hay)