Over the past couple of days, many users have complained about finding links on their Facebook pages taking them to images depicting jarring violence and graphic pornography. Although the way the latest spam messages spread isn't new, their content is more shocking than the typical scam enticing a free iPod shuffle.

The latest attack tricked users into clicking on links by offering some sort of promise — free plane tickets, a fun new video or answers to a quiz, for example, said Vikram Thakur, principal security response manager at Symantec.

Clicking on the link took users to a page that asked them to copy and paste a line of malicious JavaScript programming code into the address bar of their Web browser.

"Pasting that little message will pick up a message or picture from whatever website the JavaScript is posting to," Thakur said, adding that it doesn't matter what type of browser people use.