Did you recently receive any game/app invites from your friends for something called “Temple Run Multiplayer” during the past week or so? I logged into my Facebook account to find not one, not two, but nine of these requests. Many others received a lot more.
Accepting the invites will bring you to the “game” page, which has nothing but a Temple Run image, a play button, and a high score button. Clicking the Play button (or somewhere near the bottom) brings up a standard Facebook login window.
Logging in with Facebook would appear to do absolutely nothing, but the hidden script (in an iframe) would then proceed to randomly invite some of your friends.
At this time, this doesn’t appear to do anything dangerous besides spam and annoy your friends. Spam is quite common on Facebook and this one, like other useless spam apps, takes advantage by promising a feature to a popular application.
Have you received invites for Temple Run Multiplayer or something similar? Be sure to report the app to Facebook by clicking the link in the footer.