- The virus infection was found last month, the company says
- The infection was reported to police
- It's unconfirmed whether data on products and techniques was leaked
There is a possibility that "system information" such as network addresses was leaked from Mitsubishi Heavy servers infected with a virus, the defense contractor said in a statement.
The "possibility of the virus infection was confirmed in the middle of August," Mitsubishi Heavy Industries Ltd. -- the nation's largest defense contractor, according to Japan's Kyodo news agency -- said on its web site Monday. The virus was reported to police, the company said, because "the danger of the information leakage became clear."
The company is also investigating the incident, along with an expert team outside the company, the statement said. It is believed the "damage expansion due to the viral infection" was stopped.
However, "it was confirmed that there is a possibility that system information in part of our internal computers was leaked in the past," Mitsubishi Heavy said, adding that the information included network addresses. It was unconfirmed, however, that data "relating to our products and techniques" was leaked outside of the company, it said.
The firm found that 45 servers and 38 computers were infected with eight types of viruses at 11 facilities in Japan, including its headquarters in Tokyo and shipyards in Nagasaki and Kobe, Kyodo reported Tuesday.
"Some of the infected machines were forcibly connected to overseas web sites, leading to the leak of Internet Protocol addresses and other network system information," Kyodo said.