Does anybody know what version of DokuWiki was being run? I'd be interested to know whether this was a 0-day exploit (and if so when DokuWiki will be patched).
There are no known vulnerabilities in current DokuWiki. As soon as we learn about the nature of the problem we will release a security update if needed.
Edit: For anyone else who's curious, here's what I'm seeing from the Google cache:
<meta name="generator" content="DokuWiki Release 2008-05-05" />
There appear to have been three major releases of DokuWiki since then, so the vector could have been a previously fixed vulnerability.