Malicious or criminal attacks accounted for 57% of reported data breaches in the September quarter, followed by human errors on 37%.

The Office of the Australian Information Commissioner received 245 notifications in the period.

By sector, health service providers recorded most breaches with 45, followed by finance (35), legal, accounting and management services (34), education (16) and personal services (13).

It is the second full-quarter update since introduction of notifiable data breach rules on February 22, which require companies to inform affected individuals and the commissioner.

The office recorded 242 notifications in the June quarter, with malicious or criminal attacks accounting for 59%.

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