Qantas says it has resolved an alarming data breach that allowed people to access other passengers’ booking information through its app.

Details of the breach emerged on Wednesday, when customers reported they had been presented with the wrong account details, including other travellers’ boarding passes, points scores and status tiers.

The breach allowed users to see where the other passenger was travelling too, as well as apparently change their seats, cancel their flight or even book a flight under their name.

“I have access to the booking details, QFF numbers, status, and boarding passes of people I don’t know. Logging out and back in does nothing,” one person said.

“I was able to access full booking details, including the ability to cancel someone’s flight to Europe,” a second reported.

Qantas customer Josh Withers said he noticed an issue with the app early on Wednesday. He opened it to see details of a customer called Sam.

“It said, ‘Hi Sam’ and I instantly noticed Sam had a lot more Qantas points than I did,” Withers told the ABC.

He closed the app and reopened it – only to see details from another customer.

Qantas confirmed on Wednesday it was aware of the reports and apologised to customers.

“We’re investigating whether this issue may have been caused by recent system changes,” it said.

In a later update, the airline said the issue had since been resolved, and was not a cyber security breach.

“The issue was isolated to the Qantas app with some frequent flyers able to see the travel information of other customers, including name, upcoming flight details, points balance and status,” Qantas said.

“No further personal or financial information was shared and customers would not have been able to transfer or use the Qantas points of other frequent flyers. We’re not aware of any customers travelling with incorrect boarding passes.”

The airline also urged its customers to continue to be aware of social media scams.