Wizz Air

A technical irregularity" in the system of Hungarian airline Wizz Air, caused it to reset the passwords of millions of customers.

For security purposes, the company forced 3 million customers to reset their passwords.

Source: https://betanews.com/2019/07/20/wizz-air-password-reset/

"id": "WIZ136271222",
"linkid": "wizzair",
"type": "Data Leak",
"date": "07/2019",
"severity": "85",
"impact": "4",
"explanation": "Attack with significant impact with customers data leaks"