The head of Australia’s largest telecommunications company told a Senate inquiry on Friday that an outage last week was likely the result of an undocumented design change and a software update that was never applied to a network time-keeping device.
The disruption, which occurred the previous Wednesday, is the most recent in a series of major incidents affecting Australia’s telecommunications industry over the past several years. Thousands of customers lost phone service, wireless payment systems were knocked offline, and train operations came to a halt.
The country’s second-largest telecom provider suffered a 13-hour emergency call service outage last year, an incident that may have contributed to four deaths. That company had also been hit by a cyberattack in 2022 that exposed the personal information of millions of people, followed by a 2023 outage that left millions without phone or internet access for an entire day.
In her opening remarks to the Senate, Telstra CEO Vicki Brady explained that routine maintenance work on network timing and synchronization equipment triggered a software configuration that caused the device to reset its date back to 2006. That reset caused authentication certificates across Telstra’s network to fail, disrupting both voice and data services — including calls to the country’s Triple Zero emergency line.
Brady said the problem stemmed from an intentional design change that had been made to the device to fix an earlier fault, but that change was never properly documented. As a result, the maintenance crew had no way of knowing how the equipment would respond when it was restarted. A software update that should have been applied to the device had also been left incomplete.
“Had that software update been completed or had the design change been properly reviewed and documented post the earlier incident, and reflected in the maintenance procedure, the outage may not have occurred,” Brady told the Senate.
She added: “Our investigation will address why that design change was not documented, why the software update was not completed, and what needs to change in our controls so known risks are captured, prioritised and closed before they can affect customers.”
Brady has been with Telstra since 2016, when she joined from Singtel-owned Optus.
