Cyberattack-hit GMO says hacker threatens to disclose customer info at noon - 毎日新聞

A hacker believed to be behind an unauthorized intrusion affecting a foreign exchange trading service of Japanese internet service provider GMO Internet Group Inc. disclosed some customer information Tuesday after threatening to do so, cybersecurity sources said.

The breach targeted GMO's Onamae.com Desktop Cloud service, with an investigation confirming on Oct. 20 that an unauthorized program had been installed by a third party in server environments of some customers.

Ransom Demand

A statement from the hacker claimed information linked to GMO customers had been posted online after the company failed to respond to a ransom request. GMO CEO Masatoshi Kumagai revealed Monday that the hacker was demanding $50 million in cryptocurrency, which he said the firm will not pay.

Government Response

Finance Minister Satsuki Katayama stated that the government is urging financial institutions to defend against potential cyberattacks, noting that five foreign exchange trading firms using the GMO server service had been affected. These companies, including OANDA Japan Inc., Goldenway Japan Co. and Ava Trade Japan K.K., have reported customer impacts to the Financial Services Agency.

Katayama emphasized: "We cannot rule out the possibility of further unauthorized transactions, so we will respond with a sense of urgency." GMO is analyzing customer devices to assess the breach extent and will notify users individually once countermeasures are identified.