SecurityFocus article....
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Overview:
We have discovered a vulnerability in the Xbox 360 hypervisor that allows
privilege escalation into hypervisor mode. Together with a method to
inject data into non-privileged memory areas, this vulnerability allows
an attacker with physical access to an Xbox 360 to run arbitrary code
such as alternative operating systems with full privileges and full
hardware access.
Technical details:
The Xbox 360 security system is designed around a hypervisor concept. All
games and other applications, which must be cryptographically signed with
Microsoft's private key, run in non-privileged mode, while only a small
hypervisor runs in privileged ("hypervisor") mode. The hypervisor
controls access to memory and provides encryption and decryption
services.
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Overview:
We have discovered a vulnerability in the Xbox 360 hypervisor that allows
privilege escalation into hypervisor mode. Together with a method to
inject data into non-privileged memory areas, this vulnerability allows
an attacker with physical access to an Xbox 360 to run arbitrary code
such as alternative operating systems with full privileges and full
hardware access.
Technical details:
The Xbox 360 security system is designed around a hypervisor concept. All
games and other applications, which must be cryptographically signed with
Microsoft's private key, run in non-privileged mode, while only a small
hypervisor runs in privileged ("hypervisor") mode. The hypervisor
controls access to memory and provides encryption and decryption
services.
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