Social networking sites, sometimes referred to as "friend-of-a-friend" sites, build upon the concept of traditional social networks where you are connected to new people through people you already know. The purpose of some networking sites may be purely social, allowing users to establish friendships or romantic relationships, while others may focus on establishing business connections.
Although the features of social networking sites differ, they all allow you to provide information about yourself and offer some type of communication mechanism (forums, chat rooms, email, instant messenger) that enables you to connect with other users. On some sites, you can browse for people based on certain criteria, while other sites require that you be "introduced" to new people through a connection you share. Many of the sites have communities or subgroups that may be based on a particular interest.
While the majority of people using these sites do not pose a threat, malicious people may be drawn to them because of the accessibility and amount of personal information that's available. The more information malicious people have about you, the easier it is for them to take advantage of you. Predators may form relationships online and then convince unsuspecting individuals to meet them in person. That could lead to a dangerous situation. The personal information can also be used to conduct a social engineering attack (see Avoiding Social Engineering and Phishing Attacks for more information). Using information that you provide about your location, hobbies, interests, and friends, a malicious person could impersonate a trusted friend or convince you that they have the authority to access other personal or financial data.
Additionally, because of the popularity of these sites, attackers may use them to distribute malicious code. Sites that offer applications developed by third parties are particularly susceptible. Attackers may be able to create customized applications that appear to be innocent while infecting your computer without your knowledge.
Children are especially susceptible to the threats that social networking sites present. Although many of these sites have age restrictions, children may misrepresent their ages so that they can join. By teaching children about internet safety, being aware of their online habits, and guiding them to appropriate sites, parents can make sure that the children become safe and responsible users (see Keeping Children Safe Online for more information).
Author: Mindi McDowell
Produced by US-CERT