LOT Polish Airlines

The ground operating systems of LOT Polish Airlines were hacked which made it impossible to file flight plans for its departing aircraft stuck in Warsaw.

The system was "fixed" after five hours, which lead to ten cancellations and a dozen or more flights being delayed.

The airlines arranged hotels for the affected passengers and ensured their safety.

Source: https://www.theregister.com/2015/06/22/polish_airline_lot_flights_delayed_it_attack_pwns_flight_planning/

"id": "LOT21181522",
"linkid": "lot-polish-airlines",
"type": "Cyber Attack",
"date": "06/2015",
"severity": "90",
"impact": "6",
"explanation": "Attack threatening the economy of a geographical region"