Nissan Securities has issued a statement disclosing that it experienced unauthorized access on April 25, 2021. The statement reads as follows (translation);
Since April 25, 2021, the online trading system (trading options / futures on stock indexes, click 365, click shares 365) has been damaged due to unauthorized access by a third party.
Due to this failure, the network related to the online trading system is cut off and restoration work is in progress. At this time, we have not confirmed any adverse effect on our other networks (including our website) or online trading system, or leakage of customer information.
We sincerely apologize for the inconvenience caused to all parties concerned. We will keep you informed about the future situation.
In reporting on this incident, SecurityNext notes that ransomware may be the problem, but it is not clear from their reporting (or the translation) whether that is just their guess, or whether Nissan has actually mentioned ransomware.