Yahoo Japan admit that their new server "visited" by hackers. In its investigation, the Yahoo Japan found an illegal access in a data server that stores the user ID.
In further investigations, the Yahoo Japan managed to find a file with the data of 22 million users in it.
Yahoo's own party are not sure, whether the file is successfully retrieved by hackers. However, Yahoo did not rule out the possibility, these important files are successfully copied out of the server.
Fortunately, in the file, the data are not password (password) as well as other important information. There is only a data ID / username which is also a public information that is used when a user leaves a comment, shopping, or auction service.
If successfully stolen, then the case is considered quite large for Yahoo Japan. In 2012 alone, Yahoo users Sakura country is rumored to touch the figure of 24 million. That is, almost most of the data is successfully retrieved the user's username.
Quoted from Computer World, Tuesday (21/05/2013), the largest website in Japan has given a warning about the possibility of data taken from the server. Yahoo also provides a service that allows users to check, whether they are drawn ID data or not.
Yahoo Japan is a web site most visited in Japan, according to Alexa. Yahoo Japan version of the site is also ranked 15th globally. Majority of this version of the site which is owned mobile operator Softbank and Japan's biggest internet. Whereas only 35 percent of Yahoo shares only.