Facebook’s messaging system is widely used and very convenient, but it’s also got some serious security flaws as far as privacy is concerned. Let’s take a look:
Even non friends can message you.
The site’s default is to allow anyone, even those not on your friends list, to message you. This means a spammer or scammer can simply open an account, harvest some names from the Facebook directory (which again the default is to include everyone) and then send a message to them all containing spam, a phishing attempt or even malware.
To block anyone not on your friends list from sending you messages, click on Settings, then scroll down to privacy and click manage, and then click on Search. You’ll be presented with a check list of things people who search for you can see. This includes your photo, friends list, a link to add you as a friend, and a link to send you a message. Uncheck that one and any other items you don’t want non friends to see when you are searched for in the directory.
After you’ve been added to a thread it’s impossible to remove yourself from it or block it.
Whether you just want to excuse yourself from a chat thread or find yourself on a spammers mailing list, you’re stuck. Facebook offers absolutely no way to remove yourself or block a thread, other than the overly drastic step of deleting your FB account, which few of us would ever consider doing.
Blocking people doesn’t stop them from messaging you.
It’s true! Say you decide to block a spammer or even a friend you’ve had a falling out with. Since they’ve already messaged you, as long as they have access to that message (or a past message from you) they can still contact you. This is particularly grievous to anyone who has blocked someone due to harassment as the nasty messages will still keep coming. Again, the only solution Facebook offers is to delete your account. Shameful.
While Facebook does offer a report system it seldom does much good. It’s far better to let users be proactive and decide for themselves who they do and do not want to receive messages from. Are you listening, Facebook?