Japan's parliament rocked after malware found on three computers and a server, possibly compromising usernames and passwords used to access internal documents and emails.
Data from 480 of Japan's Lower House members was reported by local media to have been compromised, but investigators had not found evidence it was stolen. The trojan has been linked to a command-and-control server based in China, Ashai Japan Watch reported.
The infection lasted for at least a month, until August, and began after a member had opened a malicious email attachment . Security software failed to stop the trojan from downloading additional "data stealing" software.
A Lower House committee held a meeting this week to investigate the incident. Chief Cabinet Secretary Osamu Fujimura said the government would take "all possible measures" to improve security, Ashai reported.
Lawmakers use the computers to email government agencies and other Parliament members. The machines also store personal information about support groups, political accounting, and donations.
The attack comes on the heels of a malware infection that spread through machines owned by Japan's biggest defense contractor and Boeing partner Mitsubishi Heavy Industries. In that case, the company detected up to eight different instances of malware, including trojans and key loggers, in factories used to manufacture submarines, missiles and nuclear power plant components.