Japanese police have discovered a new computer program that helps hackers get unauthorized access to online services more efficiently.
The discovery comes after police arrested last May a Chinese national on suspicion of operating an unregistered server to make illicit money transfers overseas.
Police seized the server which they believe was used to relay access to the Internet from a site in Ibaraki Prefecture and found the program in the server.
Investigative sources say the program found during the analysis of the server was likely used for list-based attacks.
In such attacks, hackers access online services based on a list of identities and passwords that they have obtained illegally.
The hackers were believed to type automatically a myriad of IDs and passwords to log in to various websites.
But police now believe the newly-found program sorts out those used to log in to email accounts and find out from the content of email what online banking or digital payment services the holders of the account information use. The program then automatically catalogs the data.
Police suspect hackers use the program to make a short list of services they will target and try to get unauthorized access to the services more efficiently and more successfully.
Police are urging Internet users not to use their email IDs and passwords for other services.
Police have found about 65 million sets of IDs and passwords contained in the server.