Extent of major Qantas data breach revealed

Of the 6 million customers whose details were in the affected system, almost all have had at least some of their information stolen.

Extent of major Qantas data breach revealed

More precise details of last week's Qantas data breach can now be revealed as the company begins contacting customers with information about just how much of their personal data is in the hands of cybercriminals today.

Of the 6 million customers whose details were in the affected system, almost all have had at least some of their information stolen.

A total of 5.7 million unique customer records are impacted, 4 million of which were limited to name, email address and Qantas Frequent Flyer details.

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Of those, 1.2 million were name and email only, while 2.8 million also included the Frequent Flyer number, most of which also had their Status Tier included.

While not outlined by Qantas today, for some of those 2.8 million, described as a "smaller subset", the information also included their Points Balance and Status Credit balance - indicating a more precise targeting by scammers of those account holders.

Among the remaining 1.7 million customers, the data was only some of the above, but additionally, one or more additional fields with 1.3 million addresses leaked - these might be home, business or hotel addresses used in baggage re-delivery.

Finally, within that 1.7 million, there are many that included Date of Birth (1.1 million), phone numbers (900,000), Gender (400,000) and for 10,000 customers, their meal preference is part of the data leak.

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"Our absolute focus since the incident has been to understand what data has been compromised for each of the 5.7 million impacted customers and to share this with them as soon as possible," Qantas CEO Vanessa Hudson said today.

"From today we are reaching out to customers to notify them of the specific personal data fields that were held in the compromised system and offer advice on how they can access the necessary support services.

"Since the incident, we have put in place a number of additional cybersecurity measures to further protect our customers data, and are continuing to review what happened.

"We remain in constant contact with the National Cyber Security Coordinator, Australian Cyber Security Centre and the Australian Federal Police.

"I would like to thank the various agencies and the Federal Government for their continued support."

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None of the data stolen in the breach has appeared online or on the Dark Web at this time, though 9News understands Qantas has been contacted by a potential cybercriminal and is unable to comment further as the matter is in the hands of the Australian Federal Police.

If legitimate, those responsible will be looking to hold the data at ransom, and may leak small amounts of the data onto the web in an effort to legitimise their claims.

For now though, the advice to Qantas customers remains the same, they should be hyper vigilant and remain alert for scam calls, texts and emails purporting to be from Qantas.