I thought I was all secure on Facebook. I never give out my password and I'm usually careful what I click, but it appears that I was the victim of identity fraud on Facebook recently. I woke up this morning to see odd and offensive messages with photos in my Facebook account from a person that recently friended me. Now I don't know if that person's account was hijacked too or what, but when I went to block the person, it looked like she had already been blocked (or maybe she lost her account?). It also looked like words were exchanged via messaging, leaving me to wonder how long my account was hijacked and whether someone has been sending malicious messages to my real friends on Facebook. This is a sad day in cyberspace for me.
My point is that this craziness can happen to anyone, no matter how safe you think you might be. I've changed my password and adjusted my privacy settings to ensure that I browse Facebook with https which is supposed to be more secure than http. I've also decided that I will no longer accept friend requests from people I don't know. I'm sorry everyone has to suffer for this, but I just can't risk it.
The photo tag virus, chat virus, and others are getting out of hand. Have you noticed lots of photo tagging among your friends lately? Photos that do not relate to your friends? DO NOT click on them. Have friends been sending you odd messages on chat with suspicious links? Shut down chat and contact your friend immediately about the issue. Check out this article from Yahoo! regarding Facebook chat being hijacked. Scary thing is, once someone has hijacked your account, they can use it to do whatever they please.
Here's some security info directly from Facebook Security that I'd like to share with you: Helpful tips here and some common threats mentioned here. Be careful, and good luck!