Dukascopy Japan confirmed on October 28 that unauthorised trades had occurred in FX accounts belonging to customers who used Onamae.com Desktop Cloud, following unauthorised access to the third-party service.
The broker said it was working with GMO Internet Group to assess the situation and prevent further damage.
Dukascopy Japan said it had not confirmed third-party unauthorised access to its trading system itself or information leakage from its systems at the time of the notice.
It had changed login passwords for accounts of Desktop Cloud users suspected of having experienced unauthorised logins.
BrokersView previously reported that OANDA Japan had restricted potentially affected accounts after confirming unauthorised trades.
In an October 27 notice, OANDA Japan said some accounts had been accessed using credentials that may have leaked through the same Desktop Cloud service. It said it had not confirmed customer-information leakage from its own trading systems or internal network.
The broker asked customers who had used the service to:
Dukascopy Japan also warned that it would not request trading-account passwords or authentication codes by email or telephone, and urged customers not to pay anyone claiming they could recover lost funds.
GMO said it would not comply with attackers’ demands because doing so would not guarantee deletion of the information obtained or prevent its misuse.
In a separate October 28 update, GMO Internet said a domain hosting information purportedly related to customers had been taken down at around 4 a.m. Japan time. It said monitoring and responses to any replacement sites would continue.
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