Interest in a major summit attended by the world's economic and political leaders is being manipulated to further the schemes of an accomplished cyber espionage group, researchers warn.

Security firm Rapid7 discovered an intensifying phishing campaign being carried out by APT12, the collective believed to be backed by China's People's Liberation Army, which carried out months-long breach on The New York Times earlier this year.

According to Claudio Guarnieri, a researcher at FireEye, who blogged about the campaign on Monday, a “swarm” of malicious emails themed around the 2013 G20 Summit in Russia, due to commence next Thursday, indicates that the group is still actively targeting organisations for intellectual property and other sensitive data.

This year, G20 Summit leaders are convening in St. Petersburg, Russia, for the eighth summit since G20's formation.

After analysing several reports on VirusTotal, Guarnieri found that the mounting interest in the summit appears to present itself as the perfect opportunity for hackers aiming to gain a foothold in organisations.

In the blog post, he dissected three phishing attacks where hackers distributed malware using weaponised zip files. The malware consisted of backdoor Trojans capable of logging victims' keystrokes and downloading additional, and more sophisticated, malware on compromised machines.

According to the blog post, a Canadian user reported a suspicious file to VirusTotal on 31st May, which was meant to look like a PDF detailing agenda notes for the G20 Summit. On 16th August, a user in France also reported another spurious zip file, which was designed to appear like informational materials about the forum. Also, last week, an individual in Hungary made note of a similar executable being sent to their organisation.

In some cases, malicious attachments contained in the phishing emails copied word-for-word the real materials and press releases being distributed to groups about the event.

Based on the activity, Guarnieri concluded that the adversary behind the attacks was APT12, primarily because instructions dispatched to the malware were sent from the same IP address that FireEye also linked to APT12 activity two weeks ago.

No vulnerabilities were leveraged in any of the G20-themed ruses, according to Rapid7's research.