Doesn't anyone here find it weird that the Admins aren't telling us how they are affiliated with the group whose exploit was running? Or that they didn't explain the risks (how infection occurs, via just loading the ad and viewing it, or if one has to click on the ad, or what)? Or that they don't offer any other info on it? Just a quick "oh it was fixed, lets move on now, nothing to see".
What do you want to know?
It's a pain in the ass to track. If I go by the IP ranges, they're delivering the ZBot/Zeus trojan. If I go by whois information, they're using a exploit delivery mechanism written by someone nicknamed ExManoize. The whois information is fake but non-private, and has been used in a lot of similar drive-by exploits and fake antivirus software. The IP ranges are definitely bulletproof hosting, but once again are from eastern europe, so best of luck there.
Most trails go dead in serbia or mother russia.
The first script(included here) writes a script to another location. That script builds up a browser profile, then redirects to the exploit for the browser. All the javascript is encrypted.
If you want to see the code that runs the "end-script", I saved a (cleaned) copy here:
//THIS CODE WILL RUNS UNKNOWN - Anonymous - zBHKyydY - Pastebin.com . Visiting that with Avast will still set off your antivirus, but it's not active and I swapped out the domain.
One method of infection is a Java class. Also apparent in the code is the fact that they can write to the c drive, and that they somehow gained access to the "ShellExecute" command, which more or less means the exploit can do whatever the fuck it wants.
Paranoid twats. Everyone except for me was working on getting the infection OFF the forum so fewer people would get infected rather than trying to track down who did it. That's why you didn't get much information.
Edit: If you want to fuck around with that Javascript I posted, GO OFFLINE BEFORE YOU EXECUTE IT. I'm unsure how functional that piece is, but it's a pain in the ass to tell what was successfully disabled. Also, one alert() in that script should actually be an eval, I forgot to change it back.