Former NSW Premier and Optus senior executive Gladys Berejiklian has lost her bid to overturn findings of serious corrupt conduct.

Fees paid to the directors of Singtel – the owner of Optus – have soared by more than 80 per cent in just one year.

Almost a month after Optus suffered one of the worst data breaches in Australian history it continues to run a “completely insecure” website, says a top cybersecurity expert.