However.... in the currently active users list, what else could an Unknown Location with something like... "/index.php/impex/ with the script url here" ...mean?
when we do not know something, instead of attacking with presumptions, we have to ask...
the unknown location like you say is just something that is unknown... logically... and if in the WOL you see such location, it means that someone TRY to access that path.. .doesn't mean it does access it with success... most of the web crawlers have that url in their path because it is a known url,... most people trying to make you fear will also use that path... jut to see if you are fool enough to let it on your site.
anyway, you have to consider suggesting this problem to vbulletin.com if you really think it's a risk, because you're actually not on the official website now...