Many people treat social media as though they need to provide evidence they’re currently having fun, about to have fun, or just finished having fun. But if boasting of your vacation plans includes posting a photo of the boarding pass for your upcoming flight to paradise, you should probably reconsider.

According to Travel + Leisure, printed and virtual passes contain a wealth of personal information that can quickly be used against you. In addition to your name, the passes list a six-character passenger name record, or PNR. (Some passes may list it as a record locator or reservation code.) The PNR makes it far easier for identity thieves to access other information related to your booking, including phone number, address, or airline benefits program.

So what’s the worst that could happen? It’s possible a hacker could cancel or change your flight or swipe your frequent flier miles. If they’re really ambitious, the data could be used to extract more information from the airline—or could be used to trick you into thinking a communication is from an airline. In either case, there’s a risk more of your information or financial data could be compromised.

If you’re in the habit of printing boarding passes to use during travel, you may want to reconsider that, too. A physical pass left in the trash or abandoned in the airport or airplane could be recovered and its information used in a similar way.

Not everything on a boarding pass has sinister implications. If you see "S/O," you might be in for a stopover, or a layover exceeding four hours.

If you’re dead-set on snapping a pass photo, you can always blur out personal information. But in the end, it’s probably best to point your lens somewhere else.

This article was originally published on www.mentalfloss.com as Why 'Travel Braggers' Should Think Twice Before Sharing Their Boarding Pass on Social Media.