iiNet hacked: customers' emails, phone numbers exposed

Hundreds of thousands of iiNet customers have had their details accessed in a cyber attack, TPG says (Lukas Coch/AAP PHOTOS)

Australia's second largest internet provider has compromised the email addresses or phone numbers of hundreds of thousands of customers.

A list of about 280,000 active email addresses and roughly 20,000 active landline phone numbers were extracted from iiNet's order management system, parent company TPG has revealed.