According to an article published today on SlashGear.com. A glitch in OS X Yosemite’s Spotlight search can expose private details if you’re an Apple Mail user. The glitch exposes your IP address and other system details to spammers and other online tracking companies. The best simplest way to protect yourself by this glitch is stop Spotlight for searching Mail and Messages, by unchecking that box in the Spotlight preferences . Lifehacker has a great article tutorial on how to turn spotlight off from searching your Mail messages.