I'm on vacation, but still checking my email. Many thanks to Mickey Williams who pointed out to me that my referral log had been hacked. I'm not sure hacked was quite the right word for it - I was breaking the first rule of Secure Code - Trust User Input at Your Own Peril. The referral HTTP header is a form of user input, and I was happily echoing it back out to the site without any sort of check whatsoever. I guess I should consider myself lucky that I ended up with a page full of porn links rather than something more serious. Obviously, I've taken the page down. When I get back from vacation, I'll check the server log to see when this started happening. Anyone else blindly storing and echoing referrals should keep an eye on their log.
I asked a while ago about canonical weblog names. At the time, I wanted unify the entries in my referral log that pointed back to the same weblog. Now, I want to also eliminate bogus entries as well. Is pingback/trackback the answer?