Users with Google Reader accounts on social-networking sites should beware, warns Trend Micro.

According to SC Magazine, a Google account that is controlled by Koobface is hosting a page with a fake YouTube video. Users who click on the fake YouTube video are redirected to a compromised Web site that hosts another fake YouTube video. Visiting the site leads to user infection, resulting in the user becoming part of the Koobface botnet.

According to Trend Micro, there are about 1,300 known, unique fake Google Reader accounts that Koobface is spamming on social-network sites. Says Rik Ferguson, senior security advisor at Trend Micro:

Cybercriminals are taking advantage of Google's credibility by hiding their malicious links behind Google Reader.