The sale of Australians' Medicare details on the Dark Web, and how the federal government handles personal information, will be investigated by a sweeping parliamentary inquiry.

In July it was revealed that the Medicare card details of any Australian was available for purchase on a popular Dark Web site for just US$22.

The vendor on the site claimed to be "exploiting a vulnerability" in a government service and said they could provide the personal Medicare card details of any Australian on request, once a full name and date of birth had been supplied.

They advertised their illegal service using a fake Australian government logo, calling their listing the "Medicare Machine". Since October 2016 at least 75 sales were made through the listing.