TPG Telecom, the second largest internet services provider in Australia, has revealed that it faced a cyber attack.

TPG Telecom had been notified of unauthorised access to a hosted exchange service that hosts email accounts of up to 15,000 business customers.

Australia’s second-largest telecoms firm Optus — owned by Singapore Telecommunications – has already faced a major cyber security incident recently.

Telstra, the country’s top telecom firm, in October reported a data breach relating to a third-party provider that exposed some historical employee details.

A report from the Australian Cyber Security Centre in November blamed the jump in attacks in majority of the incidents on inadequate software updates.

TPG said the primary aim of the hacker was to search for customers’ cryptocurrency and financial information. Its cyber security adviser Mandiant discovered the breach during a forensic historical review.

“It does show to the world and to Australia that it is quite easy for hackers to access customer records, which is obviously a huge negative and a lot of the other companies should definitely be wary,” Azeem Sherrif, a market analyst at CMC Markets, said.

TPG said it had implemented measures to stop the unauthorised access and was contacting all customers on the exchange service affected by the incident. TPG Telecom does not reveal the name of its cyber security partner.

TPG Telecom reported service revenue of $2,190 million (+0.7 percent) in the six months to 30 June 2022. TPG Telecom has 5.16 million mobile customers.

TPG Telecom says its 5G network rollout is ahead of schedule, with 1,500 mobile sites completed to date. TPG Telecom expects its 5G rollout will surpass 2,000 sites by the end of 2022. TPG Telecom aims to add more than 1,000 mobile sites per year until the mid-2020s, as part of its network investment program.