Hardware hackers have developed a technique to hack Microsoft's Xbox 360 gaming console so that it might be possible to run alternative operating systems on the hardware.
The approach, which only works given physical access to the hardware and is strictly for fun, relies on a taking advantage of a vulnerability in the Xbox 360 hypervisor. Properly exploited, the bug allows tinkerers to run arbitrary code (even an alternative OS) with full privileges and full hardware access.
The hypervisor on Xbox 360 machines controls access to memory and provides encryption and decryption services. The approach means that all games and other applications running on the Xbox 360, in theory at least, need to be cryptographically signed with Microsoft's private key and run in non-privileged read-only mode.
Unprivileged code cannot change executable code, but flaws in the way unprivileged code interacts with the hypervisor via the syscall instruction laid the groundwork to the hack.
Full details on the ingenious exploit, including proof of concept code, were published on BugTraq on Wednesday. The anonymous hackers tipped Microsoft off about the issue last month and "following cordial discussions" the software giant quickly produced a patch. The hack has been possible since the bug was introduced in late October. ®