hacker discovers Facebook vulnerability, lets Mark Zuckerberg know on his wall
A Palestinian hacker recently discovered a Facebook bug that allows any user to write on anyone else's wall, whether or not they are “friends”. After notifying Facebook and not receiving an answer, he then decided to instead demonstrate the vulnerability by writing on Mark Zuckerbrg’s wall.
Unfortunately for him, this decision caused Facebook to deny him the $500 that is awarded to those who find software bugs. Maybe next time he will follow up with an email instead.