Oversharing

By harvesting the information that is available online, attackers can develop highly targeted – and effective – phishing.

Spear phishing is a highly targeted form of phishing attack that relies on information about a person to trick victims.
Malware links don’t seem so risky when they refer to people or places familiar to you or to activities you like to carry out.
In some cases hackers have been known to burgle houses when they have seen online that the occupants are aware on vacation

To protect against this, don’t neglect your privacy settings and be sensible about what you share online.