Win32:CabMod - Dropper

What Is This And What Dose It Do

My best guess is:
Cab = Cabinet file (archive file) and an iso file is like a very big cabinet/archive file as it is a whole CD image.
The [Drp] Dropper, is I guess a bit like a downloader to drop a process on to your system.

Because of its size avast can’t process it, the file ‘GUITAR HERO III INSTALLER.EXE’ would exceed the maximum file size to send to the chest. Whilst you can increase that maximum file size for the chest, I don’t know if it can actually extract the file from within the .iso file.

I would caution against running, or otherwise using this file at all.
Executables downloaded via P2P programs are fairly notorious for containing malware.

Microsoft usually have a good description of malware, so you can search here http://www.microsoft.com/security/portal/

Microsoft call this Win32/Harnig.gen