Angry compliments

For the last couple of weeks, we have been getting posts with one-line compliments on our forums, e.g.

Wow!!! Good job. Could I take some of yours triks to build my own site?

Nice, isn't it? Well, not when you get a lot of those, from anonymous posters, and accompanied by strange, and sometimes outright spammy subjects (the subject for the above post, for example, was "adipex-online").

Now, compliment spam isn't new. But those usually come with a bunch of spam links attached, sometimes openly, sometimes thinly veiled as "please visit my site".

What's interesting about this particular spammer is that all of his posts are missing the spam links. At first I thought it may only be a test run and the actual spam would start later. But by now I've come to the conclusion that it's simply a broken spambot. Which, of course, makes it a bit difficult to filter these posts. Typical keywords (as in the example above) are rare. The posts are coming from all over the place (China, Norway, USA, ...), so we can't easily block IP addresses either. And the user agent strings used by the spambot are those of browsers you don't want to block.

The only thing all these non-spam posts have in common: Even though they contain compliments, they are accompanied by an "angry" mood icon (a feature of our forum software). The author of the spambot probably thought it was a good idea to select an option from any dropdown it encounters. And in our case this happens to be the "angry" mood. Which, interestingly enough, is the second option in the mood dropdown.

I wonder if I could write a spam filter based on that information ...