If you're familiar with email marketing, it's one way companies entice you to open up an email. It may have a call-to-action-type subject line, where they're asking you to do something.
That may be promising you something, like "Act now for your chance to win." Or, it may be something that alarms you, like "This is your final warning."
As it turns out, cybercriminals are becoming more sophisticated in their email marketing efforts. That includes emails containing malware that appear to have been sent by Facebook. (See photo above.)
In this phishing scam, the cybercriminals use a subject line that could get anyone's attention. It might say, "You just received a voicemail," or "An audio announcement has been delivered."
Of course, you'll wonder what type of voicemail or audio message you're getting from Facebook. However, this is a phishing scam.