A few of my forums have been getting hit with spam bots daily . What exactly is a spam bot and where do people get this bots from ? . Cause it seems that the same spam is on other forums . So it seems that it's a program that floats around to phpbb forums and spams that same messages . I believe I found a script to add to prevent this from happening in the future. but I was just wondering how do these bots exactly work .
Since all phpbb forums are technically basically the same, it's quite easy to create a bot that does certain tasks. (I created a bot in PHP which can register, login, post messages, etc... it even could bypass phpbb's old image verification, and confirm emails). All you have to do is to send HTTP requests with specific variables to specific scripts on the server. You can use cURL for example, it even supports cookies, and emulates the rest of a normal web browser. In some cases you'll need regular expressions to fetch certain data, like verification/authentication keys, etc. Most modern bots can bypass any image verification techniques, so you'll receive less spam, but you'll still get some.
Well, most likely the script searches for known keywords for phpbb forums like "Powered by phpBB" on Google and getting all the urls of the forum sites and then because all the sign up forms are in the same place with phpbb they make the script join then like validate the captcha and get the verification link from email and then make the script add posts/topics to the forum.