The 132,000 customers had requested their phone numbers not be made publicly available, but an internal error meant the numbers were, Telstra Chief Financial Officer Michael Ackland has explained.
He has told Today that 16,000 of those customers had their phone numbers published in the online version of the White Pages directory.
“The balance of the 132,000 were not available online, but were available on directory assistance, which is a service where you call 1234 and you can ask for the phone number of an individual person,” he explained.
Ackland said the data breach was discovered during Telstra’a regular auditing processes.
“We found there were misalignments where customers, who in our databases we believed should have been unlisted, were flagged as listed in the directory assistance database, and those 16,000 customers in the White Pages database.”
He said Telstra had immediately removed the numbers for the White Pages after discovering the fault, and was working to remove the data from the directory assistance databases.
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Ackland said Telstra had contacted all affected customers and offered them free service ID care.
He said it was “fair” for customers to be feeling let down.
“It is unacceptable that this occurred. We of course apologise. Customers have every right to request their service is unlisted which millions of customers do,” Ackland said.
“We’re continuing to review and look at our processes and how we audit and reconcile the databases to ensure it doesn’t happen again.”
