Nothing new, we have such posts on a daily basis. Technically it is most likely possible, but it will require either finding and installing some mod, or coding the solution on our own - SMF only supports CAPTCHA on first posts, which would not change the situation by much (you need to pass CAPTCHA to register).
I will start looking for an automatic solution the day I will decide we had enough
![Wink ;)](https://www.chemicalforums.com/Smileys/classic/wink.gif)