BBC News
By Joe Tidy
Published
How much personal information do you share on your social media profile pages?
Name, location, age, job role, marital status, headshot? The amount of information people are comfortable with posting online varies.
But most people accept that whatever we put on our public profile page is out in the public domain.
So, how would you feel if all your information was catalogued by a hacker and put into a monster spreadsheet with millions of entries, to be sold online to the highest paying cyber-criminal?
That's what a hacker calling himself Tom Liner did last month "for fun" when he compiled a database of 700 million LinkedIn users from all over the world, which he is selling for around $5,000 (£3,600; €4,200).