Last week, Air France and KLM reported a data breach in which hackers gained access to customer data.
The airlines say internal systems were not affected and sensitive data such as passwords, travel details, Flying Blue miles, passport or credit card details were not stolen. Customers whose data could have been accessed were informed and advised to be alert to suspicious emails or phone calls.
In a statement, KLM said IT security teams took immediate action to stop unauthorised access and measures have been taken to prevent a recurrence.
This comes after a series of cybersecurity breaches affecting Qantas, Hawaiian Airlines, WestJet and SAA were reported over the past three months.