A 5-year-old San Diego boy has outwitted the sharpest minds at Microsoft — he's found a backdoor to the Xbox.

Kristoffer Von Hassel managed to log in to his father's Xbox Live account. When the password log-in screen appeared, Kristoffer simply hit the space button a few times and hit enter.

Robert Davies tells KGTV-TV that just after Christmas, he noticed his son playing games he supposedly couldn't access.

Davies, who works in computer security, says he reported the issue to Microsoft, which fixed the bug and recently listed Kristoffer on its website as a "security researcher."

A Microsoft statement says "we take security seriously" and thanks customers for highlighting issues.

It's not Kristoffer's first triumph. At a year old, he bypassed a cellphone toddler lock by holding down the "home" button.