I run a small, niche personal ads site. People post ads and then other people reply to them, which sends an email to the original creator of the ad telling them that someone is interested and giving them contact information for that interested person.
Lately there's been some weird spam. People are receiving nonsense replies to their ads. Here is an example of one:
Name: xkauwvyr
Reply: vRYmbI <a href="http://rypmoxdkfblf.com/">rypmoxdkfblf</a>, url=http://pnjlwvhizwbq.com/]pnjlwvhizwbq[/url], [link=http://hmenwoujxrfv.com/]hmenwoujxrfv[/link], http://ogsekuhoyeud.com/
They vary in length and composition but they all look roughly like that. The first idea I had was to simply throw out any reply that contained the string "
Also, is this spam just some ass playing a trick on my website, or is it something more malicious?