Verified answer

They were looking for security holes on your website. I'm dealing with the same exact thing. Notice that they are scanning for different PHP versions. Also notice the timestamps. It seems like two Apache Get requests per second (at least that's what mine was). You can do a whois on the IP to find which company owns that IP and report it to their abuse department and if they're serious in handling abuse issues they'll go to the root cause of it. You can also ask your webhosting provider for assistance in reporting this too. From my own experience, they don't do anything and it really sucks. You just have to make sure you have the latest PHP and patches as well as MySQL updates. You can also try blocking their IPs via an .htaccess file. If the IP is owned by a Russian, Romanina, or Chinese company then it is no use in reporting. :-(

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