Asked and answered many times, as a quick search would have revealed. The Xbox 360 has been available since 2005, and since then only one software exploit has been discovered - the King Kong shader exploit, which was quickly fixed. Outside of Government agencies the Xbox 360 is one of a handful of devices that have been subject to the most concerted hacking attempts, yet no further software exploits have been found. Consequently it is safe to assume that there are almost certainly no software exploits waiting to be found.
Hopefully a mod will move this to the newbie section.....
This post has been edited by Heimdall: Jun 21 2012, 12:58 PM