"While commodity VMMs conform to the PC architecture, virtual implementations of this architecture differ substantially from physical implementations. These differences are not incidental: performance demands and practical engineering limitations necessitate divergences (sometimes radical ones) from native hardware, both in semantics and performance. Consequently, we believe the potential for preventing VMM detection under close scrutiny is illusory — and fundamentally in conflict with the technical limitations of virtualized platforms."
The paper concludes by saying that
"Perhaps the most concise argument against the utility of VMBRs (VM-based rootkits) is: "Why bother?" VMBRs change the malware defender's problem from a very difficult one (discovering whether the trusted computing base of a system has been compromised), to the much easier problem of detecting a VMM.""
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