Hypervisor

From Free60 Project

Like in the PS3, Microsoft protects the integrity of its system with a hypervisor. Using the virtualization technologies of today's processors, a hypervisor can act as a small piece of code with even higher privileges than the more complex operating system. In theory, even potential flaws in the operating system cannot be exploited since the hypervisor puts up additional restrictions.

In case of the Xbox 360, the hypervisor is responsible for encryption, decryption and the enforcement of access restrictions on memory.

Thanks to the work (http://www.securityfocus.com/archive/1/461489/30/0/threaded) of an anonymous hacker, a flaw in the hypervisor has been discovered on certain versions of the Xbox 360 kernel, allowing the injection of code, which has not been cryptographically signed by Microsoft.