I found this article which talks about a rootkit which infects the VBR and creates a virtual file system in unallocated space between partitions. I know that there are MBR rootkits which cannot be deleted by simple reformat the partition and to get rid of them you have to overwrite first 512 bytes of the drive or to repartition the drive, deleting partion table and creating a new one. However this article talks about VBR, not MBR, and there is written that reformat the partition and reinstall the OS can't delete the malware. The VBR is the first sector of a partition and, according to various sites on the web, it is created when you format a partition. Of course if you just reformat the partition the virtual file system will stay in the unallocated space, but without the infected VBR nothing can execute code from it. Can someone explain how is it possible for this malware to survive an OS reinstall?