My blog has been receiving a lot of spam lately, at a rate of about 50 dummy comments per day. As my current web hosting doesn’t allow me to open socket connections, a part of WordPress functionality (including Akismet, the spam checker plug-in shipped with WordPress) won’t work. I knew about the limitations and am currently looking for a hosting replacement (in fact, I guess I already found one). In the meantime, manual triaging so much spam was just becoming painful.

In order to try finding a quick fix to the problem, I made a quick analysis to the spam comments, which revealed a pattern in about 95% of the comments: the commenter always had the URL set to something like [few random letters].com/map.html. I then added the following to my Comment Blacklist (found in Settings, Discussion):

.com/map.html
buyaccutane@gmail.com
195.88.33.85

There, this should keep me less annoyed for a while (at least, until I find the time to switch hosting).

As a final note, be careful when automatically filtering using a less significant string (for example just .com): you may end up marking desired comments as spam. Always seek for a pattern which is different enough from generally expected content.

(Post image shamelessly copied from here.)

Update 2009-11-22: Updated anti-spam rules; added post image reference.