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I have a home computer with Windows 7 64-bit Pro installed. For nearly all of what I do, this setup works great, but I have some web applications which won't work. I've experimented and discovered they work fine on a Windows XP 32-bit virtual machine (with IE 7).

I use this virtual machine very infrequently and only for web applications. I would have no problem wiping it and creating a new one if necessary, so the question is whether I need to install antivirus software on it. Is it possible for viruses to propagate from the virtual machine to the host?

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marked as duplicate by Diogo, Brad Patton, KronoS, Renan, 8088 Apr 5 '13 at 16:11

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.

up vote 5 down vote accepted

tl;dr; Yes, you should run an antivirus on the VM. *

Is it possible for viruses to propagate from the virtual machine to the host?

Technically: Yes.

There has not been a virus that affects a virtual machine through the hypervisor (that's the program you run to START the virtual machine; e.g. vmware workstation, hyper-v), however, this is a security concern.

Having written that: If your virtual machine is connected to the same network as your win7 host then you are just as vulnerable as if someone brought an infected laptop to your home network and connected it.

If you drag and drop files between the two and one gets infected inside the XP VM, then dragging it to the win7 host will result in an infected file on the win7 host.

* And keep the VM up to date. And configure a firewall. Etc etc.

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What firewall would you recommend? – JohnnyVegas Apr 5 '13 at 13:33
That depends on what you do with the machine. Several XP releases come with a build in firewall which may be good enough. (Going from memory: No firewall in XP with no SP or with service pack 1, partial FW since SP2). Using that in combination with a properly configured edge firewall should be good enough. – Hennes Apr 5 '13 at 13:43
Zonealarm was good years ago, now it's a dog. Will stick to the built in. Thanks – JohnnyVegas May 24 '13 at 17:03

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