Experts have warned holidaymakers that sharing images of your boarding pass online could leave you open to having your personal data hacked.

While boarding passes may not have your address or phone number, they still have lots of codes on them which could be used to find our information about you.

This includes frequent flyer numbers, your flight number and your name.

Some airlines have online systems which can be logged into with just this basic data.

The barcode on the document could even bring up details such as passport numbers.

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Privacy researcher Bill Fitzgerald told Conde Nast Traveler: “If you have a barcode on something […] you should definitely never be posting it on social media.”

“If you’re concerned about having your identity stolen, it’s a really simple step to take, to not share barcodes in any way, shape, or form.”

Caleb Barlow, president and CEO of cybersecurity consulting firm CynergisTek agreed, telling Forbes that to break into a frequent flyer account, “all you need is your name, your booking reference number and your frequent flyer number. All three of those things are on the boarding pass”.

He added: “There could be a couple of basic password reset questions – but I might be able to get the answers to those just by looking on the web. And now that I’ve got your frequent flyer account.”

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You should never throw it out either, in case someone gets hold of it – so shredding it after your trip is advised to keep your personal information safe.

You shouldn’t throw your boarding pass away for another reason as it could get you some extra discounts on holiday, with hotels and airlines offering more money off with it.

Even mobile boarding passes can cause problems, due to third party tracking resulting in potential breaches.

The best option? Taking a picture of your boarding pass and then keeping this in your photos folder on your phone, Bill said.

There are lots of boarding pass codes you need to know about too.

If you see SSSS on it, you could end up being late for your flight.

The code stands for “Secondary Security Screening Selection” which means that the passenger has been selected for additional screening by security.

Anyone with this code is advised to turn up an extra half hour early for the airport, because getting through security will take considerably longer than usual.

And if you see GTE on your boarding pass, it might mean you don’t have a seat on a plane.

One traveller revealed how he was given a boarding pass with GTE on it after he checked in at the airport rather than online – and had to find a seat on a different flight instead.

This article originally appeared on TheSun.co.uk and has been reproduced here with permission. 

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