Optus has sent out thousands of letters to apologise for leaking some of its private customers details, including their name, phone number and home address.
This information appear in its physical and online White Pages directories.
Some customers who received the letter dated to October 1 posted it online.
"As soon as this issue was discovered, we contacted Sensis to remove your details from their online website directory, operator-directory assistance and any future printed editions of the directories. However, your details may still remain printed in older versions of the White Pages," Optus' apology letter read.
"Once again we're very sorry for this mistake. We’re contacting all affected customers and we’ll continue to conduct audits to ensure that your personal information is treated with the greatest care."
The letter outlined customer details were accidentally published in the following areas:
- Listed online at whitepages.com.au.
- Potentially listed in the local printed White Pages.
- Listed with operator directory assistance.
- Possibly listed in other smaller online directories.
An Optus spokeswoman told Yahoo Finance many of the leaked customer details were already available on Sensis but Yahoo Finance confirmed Sensis denied any responsibility.
"The majority of the affected customers' details were already listed with Sensis prior to joining Optus," an Optus spokeswoman told Yahoo Finance.
If you believe you've been affected by this data breach, you can call Optus on 1800 234 020 between 9am and 5pm Monday to Friday.
The ACCC has just announced that the Federal Court has ordered Optus to pay $10 million for misleading customers. Proceedings against Optus began in October 2018, with the order being handed down today. In a breach of corporate regulations, some Optus customers unknowingly bought digital content such as ringtones and games through third party billing services.