Malware From Ad Widget

While visiting one of my many blogs (not this blog), a warning message suddenly popped up covering the whole page in red. It was a message from my browser. Shown below is the screenshot of the message.

What? Malware in my blog? So that's what I get from taking ad widgets from just anyone out there. The culprit is Pay-Ads.com . The message from Chrome browser says :

Warning: Visiting this site may harm your computer!
The website contains elements from the site www.pay-ads.com, which appears to host malware – software that can hurt your computer or otherwise operate without your consent. Just visiting a site that contains malware can infect your computer. For detailed information about the problems with these elements, visit the Google Safe Browsing diagnostic page for www.pay-ads.com.

I installed an ad widget of pay-ads.com three or four months ago in one of my blogs (not this blog) and completely forgot about it. Now that I get this warning message from my browser I immediately uninstalled the bloody widget but Chrome continues to tell me that that blog has malware.

What is the moral lesson of this story? Never ever install widgets to your blog if you are not really sure about the source.