Came to check on my new favorite thread and bam! got me again. I wasn't fast enough to monitor the whole process, but these were the sites that it redirected me to:
http://fqu0461en17kywpagpfc07t51454e....ie/index2.php
=>
http://erbj9d8q83skh9kwd99hhff.1gayp...exts&t=timeout
=>
http://adultfriendfinder.com/go/page...lpo_redirect=1
You can block this action on your own machine, Windows is easy, I think Mac is about the same, but Android can't be done without rooting and I doubt IOS allows you the access. Here's an example:
http://www.wikihow.com/Use-a-Hosts-File-in-Windows . You can block the first two sites, but I doubt they stay the same. Blocking adultfriedfinder should be a permanent fix though. You might want to find a hosts file to copy/paste into your machine that has a lot of this garbage already weeded out.
Rich, I would check the ad server / actual ads like you mention, and I would also check to see if your vbulletin templates have been modified recently. This is a pretty old version of vbulletin and the bad guys know how to hack it and add themselves as admin. Then they drop a little script in here or there and often go unnoticed. If this is the case it wouldn't be any actual files on your server, just an html snippet within the template or database somewhere.
It's definitely not anyone's computers, but an issue delivered by the servers involved. It probably has nothing to do with what anyone's personal setup is. But yes, cleaning your own machines afterward is a definite good idea.