JAL Customer Data Target of Cyber Attack

TOKYO--Japan Airlines Co. said it has become the latest target of hackers, with the information of up to 750,000 customers possibly stolen.

The airline confirmed Monday it has found evidence of unauthorized access to its Customer Information Management System due to a virus attack on computer terminals within its network. The personal data of JAL Mileage Bank members are stored in the system.

The data that may have been leaked include the names, genders, birth dates, addresses, email address and places of work of JAL's mileage program members.

The airline said there is no indication that the members" passwords or credit card numbers have been stolen.

JAL found out about the leak as it conducted an investigation into incidents where its customer information system responded too slowly on Sept. 19 and 22.

It said personal data of approximately 190,000 customers are suspected to have been stolen on the two days. Of those, a maximum 21,000 pieces of data were likely to sent to "a malicious external server," which the company hasn't been able to identify except that it is located in Hong Kong.

JAL said the data breach may have already begun Aug. 18, which means up to information on 750,000 customers could have been leaked in the worst case scenario.

While JAL's information systems have never been hacked before, it wasn't the first time for a Japanese airline to become the target of illegal system access.

In March, All Nippon Airways Co., JAL's domestic rival, saw 11 cases where flight mileage credits of its customers were exchanged for gift codes for Apple Inc.'s iTunes store without the users" authorization. The company said that no personal data were stolen at that time, though it hasn't determined how the incidents occurred.

"We are taking necessary measures and have blocked the ability for all computers with access to the affected system to connect to external networks," JAL said in a statement.

"Based on findings of our investigations, we will take all possible countermeasures," it added.

Write to Megumi Fujikawa at [e-mail]

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