In addition to Mr. Obama, the leaders whose information was disclosed included David Cameron of Britain, Xi Jinping of China, Angela Merkel of Germany, Narendra Modi of India, Shinzo Abe of Japan and Vladimir V. Putin of Russia. Australia did not inform the leaders, The Guardian reported.

The personal information included the leaders’ names, dates of birth, titles, positions, nationalities, passport numbers, visa grant numbers and visa subclass, according to an Australian government document detailing the episode and obtained by The Guardian. Most of that information is publicly available. The White House would not say whether it had changed the president’s passport number as a result of the breach, or if it would.

According to the document, the assistant director of the visa services support section of the Department of Immigration and Citizenship intended to send the information about the 31 leaders to another official “to assist in the department’s overall management of visas” for the G-20 summit meeting. Instead, because of the email program’s auto-fill feature, the message went to someone who worked for the organizing committee of the Asian Cup soccer tournament.

The mistake was noticed within 10 minutes, the document said, and the recipient deleted the email and then emptied his deleted items folder. The sports committee assured the Australian government that there was no record that the email had been forwarded or copied, and that it was not recoverable or stored elsewhere in its system.