Hackers are attempting to download malware to users' computers by dressing it up as a feature to upgrade the "Hangouts" facility of the Google+ social network.
The deception begins with an email inviting users to download a plug-in for free videoconferencing service Google Hangouts.
Security website Malwarecity.com received a copy of the email, which claims to enable users to "Look and sound your best with high quality audio and video".
However, when the user clicks the button claiming to install the plug-in, the malware attempts to download an executable file, which in this case is a trojan.
If allowed to complete, this would most likely contact a server operated by the malware author, which would then download further malicious code.
Security firm Kaspersky noted through its news service that it has so far seen very little malware targeting Google+, but that this could be set to increase as the site grows in popularity.
"G+ specific malware and attacks have been far and few between. That may change, however, as the size of the nascent social network continues to grow."
Facebook and its users by contrast are under constant cyber assault, with the recent Koobface worm infecting hundreds of thousands of machines and netting its authors a reported £1.3m.