Hi, we have a Joomla site with k2 installed. Our normal hosting bills are 40$, but last month, I received a bill of 465$ . I got blank for a moment!

Then when I started looking at my CPU usage of server, I saw there were few 4-5 URLs, which ate like 60-70% of CPU all throughout the month.

I found out, they were a K2 activated module page. I checked K2 backend and it had like 30-40k comments , which came from no where. Even I had the comments switched off in the backend, I dont know, howcome the comments got into the k2 database.
I uninstalled K2 and now its fine.

But the pages are still eating CPU, but very less. I guess, the spam softwares are still trying to access those k2 pages.

So, how do we track this and fix or solve it ?

I dont see any reply on this and its over 3 months.

Did I ask something wrong ?

You need to either enable reCaptcha or Akismet. Both have their settings in the K2 params.

As for blocking site suckers you need to edit your site's .htaccess file. There are several available examples on the net.