Why should a person never share pic of boarding pass online?

Barcode on boarding pass can contain key data, including passenger name, PNR, flight details, seat number and sometimes even frequent flyer information, said aviation expert K Anuradha Suresh, retired Senior AGM at Air India. A malicious person can log into airline's 'Manage My Booking' portal, change or cancel passenger's seat, or cancel flight. It could also lead to identity theft.