I’m not even sure what the utility of trackbacks are, but I have the feature enabled on my Drupal site. Unfortunately, I discovered that this made the site susceptible to junk trackbacks.
Given that I only vaguely understand what they’re for, I should probably just disable the feature altogether. When the concept first came up, I was running Userland Manila and trackbacks didn’t make sense to me then — let alone now.
The response I’ve taken tonight is to enable a spam filter for Drupal that will scan trackbacks. I’ve also taken the liberty of deleting all of the existing junk — most of the identifiable source addresses came from Russia — to prevent these many tiny messages from clogging up my database. One set of queries, I kid you not, deleted over 3,000 database entries in one fell swoop.
This is an unfortunate state of affairs. Trackbacks are apparently just one more piece of social software that can get spammed. Sigh.