VMworld 2006: How virtualization changes the security equation
This session was very well attented (roughly 280 people), which is encouraging. In the following, I will mix all the panel responses together without differentiating the sources.
It was said that virtualization can make security more acceptable, by contrast to past security solutions and suggested practices that used to be hard to deploy or adopt. Virtual appliances can help security by introducing more boundaries between various data center functions, so if one is compromised the entire data center hasn’t been compromised. One panel member argued that virtual appliances (VA) can leverage the expertise of other people. So, presumably if you get a professional VA it may be installed better and more securely than an average system admin could, and you could pass liability on to them (interestingly, someone else told me outside this session that liability issues were what stopped them from publishing or selling virtual appliances).
I think you may also inherit problems due to the vendor philosophy of delivering functional systems over secure systems. As always, the source of the virtual appliances, the processes used to create them, the requirements that they were designed to meet, should be considered in evaluating the trust that can be put into them. Getting virtual appliances doesn’t necessarily solve the hardening problem. Except, now instead of having one OS to harden, you have to repeat the process N times, where N is the number of virtual appliances you deploy.
As a member of the panel argued, virtualization doesn’t make things better or worse, it still all depends on the practices, processes, procedures, and policies used in managing the data center and the various data security and recovery plans. Another pointed out that people shouldn’t assume that virtual appliances or virtualization provide security out-of-the-box. Out of all malicious software, currently 4-5% check if they are running inside a virtual machine; this may become more common.
It was said that security is not the reason why people are deploying virtualization now. Virtualization is not as strong as using several different physical, specialized machines, due to the shared resources and shared communication channels. Virtualization would be much more useful on the client side than on the data center for improving security. Nothing else of interest was said.
Unfortunately, there was no time for me to ask what the panel thought of the idea of opening VMware to plugins that could perform various security functions (taint tracking and various attack protection schemes, IDS, auditing, etc…). After the session one of the panel members mentioned that this was being looked at, and that it raised many problems, but would not elaborate. In my opinion, it could trump the issue of Microsoft (supposedly) closing Windows to security vendors, but they thought of everything! Microsoft’s EULA forbids running certain versions of Windows on virtual machines. I wonder about the wisdom of this, as restricting the choices of security solutions can only hurt Microsoft and their users. Is this motivated by the fear of people cracking the DRM mechanism(s)? Surely just the EULA can’t prevent that—crackers will do what they want. As Windows could simply check to see if it is running inside a VM, DRMed content could be protected by refusing to be performed under those conditions, without making all of Windows unavailable. The fact that the most expensive version of Windows allows running inside a virtual machine (even though performing DRMed content is still forbidden) hints that it’s mostly due to marketing greed, but on the whole I am puzzled by those policies. It certainly won’t help security research and forensic investigations (are forensic examinators exempt from the licensing/EULA restrictions? I wonder).