Even Facebook founder Mark Zuckerberg is not safe from cyber attackers.Zuckerberg's Twitter, LinkedIn and Pinterest profileswere briefly hacked over the weekend.His Facebook and Instagram accounts were not involved, Facebook officials said.A group calling itself OurMine Team said it attacked the three accounts on Sunday,according to the website TechCrunch.The accounts were quickly restored.Twitter says a Twitter account used by the hackers to post messages was suspended.A website called Engadget captured messages posted by the hackersto Zuckerberg's personal Twitter account."We are just testing your security,"said one message posted by the hackers to the billionaire's Twitter profile.Zuckerberg had not posted anything to his Twitter account since 2012.Business networking site LinkedIn confirmed Mondaythat the Facebook founder's data was compromised, The New York Times reported.The company said the hackers attempted to create a false profile for Zuckerberg."We were alerted of this takeover attemptand have taken action to remove the false profile on LinkedIn,"said a statement, the newspaper reported.The hackers also posted what they claimed was the passwordused for Zuckerberg's LinkedIn account.But LinkedIn did not say if the attacks on Zuckerberg's social media accountswere part of a large data breach at the company in 2012.That leak, of emails and passwords, affected more than 100 million LinkedIn accounts.Internet security experts suggest that userschange their passwords often to keep accounts safe.They also warn users not to use the same passwordsfor different social media accounts.