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Virtual Machine and Virus
I am running a virtual machine on VirtualBox. Assuming that I have no shared folders between the host and guest OS, is the guest OS completely sandboxed? (eg I could fill that VM with horrible viruses/rootkits/malware and it could never affect my host OS?) Or is there some way for a program to detect that it is in a VM and escape to/cause damage to the host OS?
I'm running Windows 7, but I'm curious about the general case.