I was just looking through my logfiles (I tend to do that whenever I get a bit tired, but don’t go to sleep) and I realized that the number of spam attempts has decreased heavilly. From blocking more than 30 attempts a day, all the way down to 52 attempts throughout June and no attempts at all in August or September. Same goes for blacklist redirects (ie. blacklisted hosts being redirected to a customized 404 page saying that they’ve been blacklisted.)

I’m not quite sure what to make of this, because there are a couple of things involved and the decrease started just as I made some big changes to my anti-spam system. The following are some possible factors in the decrease and there may very well be some I’m overlooking.

I started returning 404 Not Found on blacklist redirects instead of 200 OK

Are the spammers running some kind of automated learning, so once they receive a 404, they stop trying? That would be weird, because in order to even see the before mentioned 404, they have to make at least 3 attempts at spamming. So automated learning would be indicated by a vast amount of blocked attempts compared to the number of blacklist redirects, which is not the case here - both numbers have decreased heavilly, though the number of blacklist redirects varies from zero to 5-6 a day.

phpCF is working great

If the spammers are in some way measuring their success-rate, then it must mean that phpCF is working great, because no spam has gotten through in a long time. But this would also be strange, because how would they measure the success-rate? Googling? I think not.

The blacklist is complete

I’ve finally blacklisted each and every spam-bot on the planet! Yay, for me! :-p
Actually, this would explain the small number of blocked attempts compared to the larger amount of blacklist redirects. But still, somehow I don’t believe that this is the reason.

More options

Last, but not least, there may be outside factors causing the decrease (even though I’d like to think that I came up with the “cure for the cancer”). Maybe Google-bombing has gotten harder, or the spammers are getting more cautious - or maybe blog-spamming just isn’t profitable enough…

… and then there is all the stuff I can’t think up right now because it’s 8:46 AM and I haven’t slept yet. If you have any ideas, experiences, thoughts … anything! Please, post a comment or drop me a mail. I’d be more than happy to know what you think.