sydneymedibank private ltd said it has withdrawn its fiscal 2023 outlook for policyholder growth as a result of an escalating cyberattack with plans to provide a further update at its firsthalf results the australian health insurer said it is currently estimating it will take a 25 million australian dollar 16 million to a35 million nonrecurring hit to its firsthalf earnings but it said this doesnt include further potential customer and other remediation regulatory or litigation related costs this cybercrime event continues to evolve and at this stage we are unable to predict with any certainty the impact of any future events on medibank including the quantum of any potential customer and other remediation regulatory or litigation related costs said medibank the company said the investigation into the cyberattack which was first disclosed earlier this month was continuing it first said that no customer data appeared to have been accessed in the cyber incident but last week it said it received a sample of records for 100 policies suggesting customer information was compromised the insurerk said wednesday it had now established that all of its ahm international student and medibank brand customer personal data and significant amounts of health claims data were accessible by the hacker as previously advised we have evidence that the criminal has removed some of our customers personal and health claims data and it is now likely that the criminal has stolen further personal and health claims data medibank said the company expects that the number of affected customers could grow substantially on tuesday the company said premium increases for medibank and ahm customers would be deferred until jan 16 in a wednesday update to its fy 2023 outlook provided in august medibank said its underlying net claims expense per resident policy unit continues to track below the fiscal 2023 outlook of 23 this it said had resulted in further permanent net claims savings due to covid19 of approximately a62 million which would offset the cost of the deferral of premium increases the cyberattack is subject to a criminal investigation by the australian federal police the insurer said