Traveling this holiday season? You might want to think twice before throwing your boarding pass away after a flight.
A new report from computer security expert Brian Krebs found that the barcodes on boarding passes contain a lot of personal information that is easily accessible to anybody with a computer.
Using a barcode reader found online, people can determine someone's frequent flyer number and other personal information from their boarding pass. It doesn't even have to be a physical copy; a picture of a plane ticket displayed on Facebook or Instagram will do.
Even worse, with a little bit of detective work on social media and airline websites, it's possible to see information about current and future flights. Someone could gain access to a traveler's account and "change seats for the ticketed passengers, and even cancel any future flights."
Related: How to Avoid Airline Baggage Fees
"There's more information on a boarding pass than you can read," security expert Bruce Schneier told NBC News. "And it can be used in ways you haven't thought of."
So how can people protect themselves? First, they can resist the urge to post photos of their boarding passes online. And there is one more obvious solution.
"It's easy," Schneier said. "They can shred their boarding passes."