A white hat hacker named Khalil from Palestine had submitted bug reports to Facebook about a glitch that allowed him to post on anybody's wall. Facebook ignored his report, so the concerned hacker took matters into his own hands by writing on Mark Zuckerberg's wall to get his attention.

Khalil had submitted a full description of the bug, and follow-up proof of its existence to the Facebook security feedback page - researchers can win rewards amounting to $500 for discovering significant vulnerabilities.

He tried again, but he received an email reply saying that it wasn't a bug. So he posted on Zuckerberg's wall saying, "First sorry for breaking your privacy and post to your wall , i has no other choice to make after all the reports i sent to Facebook team ." He then detailed the situation, complete with links.

A Facebook engineer contacted Khalil minutes later for more information and blocked his account "as a precaution while a security team fixed the bug. His account was re-enabled later, but Facebook said he couldn't claim a reward for the find in hacking Zuck's wall because he violated the social network's terms of service.

They said "exploiting bugs to impact real users is not acceptable behavior for a white hat. In this case, the researcher used the bug he discovered to post on the timelines of multiple users without their consent."

And all Khalil wanted to do was good. Oh well, at least we know our walls our safe?