After checking email and reading articles or books, using social media sites is the third most popular activity on the Internet, and the second most popular on mobile devices.

While doing so, 15% of users share information online that they would not disclose in real life, according IT security firm Kapersky Lab’s global "Consumer Security Risks Survey for 2014."

Even seemingly innocuous information can present a danger. For example, an email address can be used to help an attacker break an account password or identify a person’s location.

Access to an account can allow cybercriminals to send malicious links and files to the victim’s friends, stealing their personal data as well.

Most customers enjoy a false sense of security: more than three-quarters of respondents believe they are just not of any interest to cybercriminals. Yet 40% of those surveyed had received suspicious emails or social media messages with unknown links or potentially malicious files, and 21% received emails claiming to be from a social media network asking for personal credentials.