Google's AdSense network is used by millions of publishers and websites to show ads on their respective platforms - and to generate money.
The service works seamlessly, but according to a new report from KrebsonSecurity, some of these sites are being targeted with a scary new scam aimed at extorting bitcoins.
Here's all you need to know about it.
Websites' owners being threatened via emails
According to the report, some websites using the Google AdSense network to show banner adverts are being targeted with email threats.
In the message, the sender warns the owner that they would bombard their site with fake, bot-generated traffic to trigger the anti-fraud systems that Google has built into the AdSense network to make sure that ad clicks are legit.
They threaten to get site, AdSense account suspended
Google follows a strict policy regarding traffic authenticity, and triggering the anti-fraud system could force the company to suspend the site in question or block it completely from AdSense.
This is exactly what the scammer threatens to accomplish unless the owner of the site agrees to pay as much as $5,000 in bitcoins to hold off the fake-traffic attack.
Scale of the scam remains unclear right now
At present, the scale of the scam is not exactly clear; KrebsonSecurity reported one case where the site owner got the email and witnessed substantially increased invalid traffic in Google's AdSense report.
Notably, as more than 11 million sites use AdSense, there is a good chance that many more may have been targeted with similar extortion threats.
However, Google says it's not a point of concern
In response to reports related to this issue, Google claimed that it has safeguards in place to detect this kind of sabotage and take it into account while calculating ad-clicks.
The company added that "it's extremely rare in practice" and advised publishers to "disengage from any communication or further action with parties that signal that they will drive invalid traffic to their web properties."