Virtuata uses the XenClient extensible virtualization Service VM architecture to establish a dynamic root of trust. By design, the XenClient hypervisor acts as the Trusted Computing Base (TCB). It then enables Virtuata to extend the trust dynamically to loadable legitimate executable programs forming a dynamic root of trust. Once running, only the code belonging to those good programs can run. By preventing good apps from getting infected, they lock out the sorts of advanced threats (like code exploitations and injection and return-oriented attacks) that have been leading headlines for the last couple of years. Thus, rather than waiting for the attack to happen and then reactively publishing signatures to detect that particular attack, they proactively protect known good and legitimate programs directly in memory.