Oxfam Australia is investigating a cyber attack that might have compromised data, including that of the charity's supporters.
In a statement, Oxfam confirmed that it became aware of a "data incident" late last week and immediately launched an investigation.
"Oxfam Australia's priorities are confirming the type of data that may have been accessed and whether or not there are any impacted individuals," chief executive Lyn Morgain said.
"We assure our valued supporters that we are treating the matter with the utmost seriousness."
The matter has been referred to the Australian Cyber Security Centre and the Office of the Australian Information Commissioner.
"This is a complex issue and inquiries are in their early stages," Ms Morgain said.
"We have also taken immediate steps to further secure our environment and leading IT forensic experts have been engaged to conduct an investigation."
Oxfam has been contacting supporters and stakeholders to inform them of the suspected breach.
The long-standing charity is part of a global network which works to combat social disadvantage and poverty.
