Last month, Yahoo! Japan disclosed that it had discovered that malware inserted in its system had extracted user data for 1.27 million users, but that the breach was stopped before it leaked any of the information outside of the company.
Now, in what appears to be an unrelated incident, the company reports that it suspects up to 22 million user IDs may have been stolen during an unauthorised attempt to access the administrative system of its portal.
The breach reportedly does not involve passwords.
Read more on Fox Business.
In related coverage, Phys.org reports:
“We don’t know if the file (of 22 million user IDs) was leaked or not, but we can’t deny the possibility given the volume of traffic between our server and external” terminals, the company said in a statement late Friday.
Read more on Phys.org.