Kristoffer von Hassel

Kristoffer von Hassel is the world's youngest known hacker and notable for being the youngest "security researcher" listed on Microsoft's Security Techcenter as having exposed a security vulnerability. At the age of 5, Hassel exposed security lapses in the Microsoft Live Xbox system, prompting wide media coverage, with some journalists highlighting the dropping age of hackers and their technology mastery.

Hassel is the son of Robert Davies, who works in computer security, and Jill Nyahay. They live in Ocean Beach, California. When the media started covering Hassel in early April 2014, he was enrolled in Kindergarten.

After wanting to play his father's video games but having parental blocks preventing it, five-year-old Hassel tried hacking into the Xbox Live system by trying different combinations of passwords. Eventually, he found a back door security glitch that allowed him first to enter the wrong password, then in the following screen to enter a series of spaces to unlock the system. After he had "exploited the security hole", Hassel's parents found him playing the restricted video games and asked him how he gained access. After he showed them, Davies contacted Microsoft to let them know about the security problem. Microsoft responded “We’re always listening to our customers and thank them for bringing issues to our attention. We take security seriously at Xbox and fixed the issue as soon as we learned about it.” They also provided Hassel with a free year-long subscription to Microsoft Live Gold, four video games and $50USD.

On its website, Microsoft has listed Hassel as one of its Security Researchers, of whom he is the youngest. Of the people listed on the page as security researchers, he has been called "the most unusual but perhaps the most significant".

Davies has stated that Hassel had also learned "three or four other hacks" by the age of five, including how to bypass smartphone screen locks.

Hassel has been identified as the world's youngest hacker, beating out others who have also been quite young. The Huffington Post has reported on "teenage tech geniuses" and The New York Times has stated "in some hacking circles, 15 would be considered middle aged." They continue to say that the age for hacking, coding, and tech adaptability continues to drop. Ages of other young hackers have included:

• 12 years old: In 2013, a Canadian boy from Quebec became the youngest person to face courts for "a slew of charges", including DDos attacks, copypasta website vandalism, exploiting security holes and posting stolen information online. His name was not released to the media due to his age.
• 14 years old: In 2011, a fourteen-year-old boy called Jake from Dublin, Ireland, hacked into the Call of Duty: Modern Warfare 2 servers and started a phishing scam to try and collect user information. It was reported that Microsoft was "develop[ing] his talent for legitimate purposes", but later Microsoft denied that claim.
• 14 years old: In 2012, "child prodigy" Aaron Bond, who was also known as "Europe's youngest app designer" was expelled from his school after hacking in to see personal records of faculty. At 14, he was also the managing director of his own web design firm, had created six apps, and was a delegate to attend the 2012 Apple Conference.
• 15 years old: In 1999, a fifteen-year-old American boy named Jonathan Joseph James, who used the internet handle c0mrade, hacked into NASA's security system and caused a 21-day shutdown. He admitted accessing 13 computers at the Marshall Space Flight Center in Huntsville, Alabama, and installed a back door for access, gaining 19 usernames and passwords of employees. He became the youngest person to ever be incarcerated for cyber crime in the United States.

• "Teen Hackers: 10 Stories of Young Code-Crackers". Huffington Post. 18 July 2012. Retrieved 8 April 2014. 
• Glenny, Misha (8 March 2012). "Tap Into the Gifted Young Hackers". New York Times. Retrieved 8 April 2014. 
• Matthews, Lee (28 October 2013). "12-year-old computer hacker is youngest ever to face charges". Geek. Retrieved 8 April 2014. 
• Jackson, Nicholas (9 June 2011). "The Youngest Troublemaker". The Atlantic. Retrieved 8 April 2014. 
• Sherriff, Lucy (3 August 2012). "Aaron Bond, 14-Year-Old App Designer, Expelled From School Over Hacking". Huffington Post. Retrieved 8 April 2014. 
• Wilson, Catherine (22 September 2013). "15-Year-Old Admits Hacking NASA Computers". ABC. Retrieved 8 April 2014.