BitMEX says its internal processes "failed" last week, subsequently exposing thousands of the exchange's clients to privacy risks.
Data provider Skew says BitMEX has some 22,000 daily users, though the number of email addresses exposed is likely significantly higher.
With major email servers imposing restrictions on bulk emailing, the firm said:
The exchange said it sends emails to all users very rarely, the last one of this size shipping in 2017. To expedite the process, the exchange's email systems API was changed at the last minute, but did not undergo the typical checking process.
“BitMEX is a global business that sends emails to many different email providers,” said deputy chief operating officer Vivien Khoo in the blog posting. “Unfortunately, this makes the job of large services such as BitMEX difficult at times.”
The exchange says it stopped further batches of emails being sent out upon recognition of the issue.
In response to the leak, BitMEX says they employed password resets and human review on endangered accounts. All users lacking two-factor authentication (2FA) and also holding account balances had passwords reset after the exchange noted hostile attempts to access accounts.
In an email to CoinDesk last Friday, Khoo reiterated that no other personal information was divulged.
BitMEX CEO Arthur Hayes image via BitMEX
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