The personal details of some of the most powerful people on the planet were accidentally emailed to organisers of a regional football tournament by the Australian immigration department.
Details such as the passport numbers, visa information and other personal data of world leaders at last November's G20 summit in Brisbane were inadvertently passed on by the Australian government during the security breach.
The details were sent to the organisers of the Asian Cup football tournament by a sole employee at Australia's Department of Immigration and Border Protection in what is being called "human error", according to the Guardian.
Prime minister David Cameron, US president Barack Obama, German Chancellor Angela Merkel and the Chinese President Xi Jinping are among those whose details were leaked.
The world leaders were not told about the data breach at the time of the incident and the error was reported less than 10 minutes after it occurred.
An email sent to the Australian privacy commissioner from the immigration department, obtained by the Guardian via Freedom of Information request, said: "The personal information which has been breached is the name, date of birth, title, position nationality, passport number, visa grant number and visa subclass held relating to 31 international leaders [ie prime ministers, presidents and their equivalents] attending the G20 leaders summit.
"The cause of the breach was human error. [Redacted] failed to check that the autofill function in Microsoft Outlook had entered the correct person's details into the email 'To' field. This led to the email being sent to the wrong person.
"The matter was brought to my attention directly by [redacted] immediately after receiving an email from [the recipient] informing them that they had sent the email to the wrong person.
"The risk remains only to the extent of human error, but there was nothing systemic or institutional about the breach."
The immigration officer who sent he email said it is "unlikely" the information is still in public domain, with the Asian Cup local organising committee adding they do not believe the email is "accessible, recoverable or stored anywhere else in their systems".
The officer advised it would be best if the leaders were not informed about the breach due to its low-level risk.
"Given that the risks of the breach are considered very low and the actions that have been taken to limit the further distribution of the email, I do not consider it necessary to notify the clients of the breach," the officer added.
It is unclear whether the world leaders have now been informed since the leak on 7 November 2014. The office of the Australian immigration minister, Peter Dutton, has yet to respond to the reports.