Hackers accessed the court recordings database in Victoria and disrupted the audio-visual in-court technology network, impacting recordings and transcription services, an official said.
Recordings of some court hearings between November 1 and December 21, 2023 may have been stolen, Court Services Victoria CEO Louise Anderson said in a statement.
Some hearings before November 1 may also have been affected, she said.
"The potential access is confined to recordings stored on the network. No other court systems or records, including employee or financial data, were accessed," Anderson said.
Hearings in January would proceed after the affected network was isolated and disabled, and court officials were working closely with the government's cyber security experts.
Court Services Victoria did not reveal whether it received any ransomware demands.
State-sponsored cyber groups and hackers have stepped up their assault on Australia's critical infrastructure, businesses and homes, a government report released in November 2023 showed, with one attack happening every six minutes.
The cyber intrusion at the court database comes after a hack late last year at DP World Australia, one of the country's largest ports operators, that forced it to suspend operations for three days.
Last week, car dealership group Eagers Automotive said a cyber incident hit its IT systems.
