The affected websites hit by the data breach are Recalls Australia, Product Safety Australia, SCAMwatch and the Australian Consumer and Competition Commission (ACCC) Public Registers website.
The email addresses of some subscribers to the watchdog information alert services were inadvertently made accessible online, it said today.
These were not indexed by search engines or linked from a web page on the sites, and could only be found if specific URLs were tried. It is not yet clear how many users have been affected or how long this has been an issue.
The ACCC says the issue was resolved as soon as it became aware and is investigating how it occurred.