Hong Kong-based crypto company Mixin announced on Sunday that it was breached and that the hackers stole around $200 million.
“In the early morning of September 23, 2023 Hong Kong time, the database of Mixin Network’s cloud service provider was attacked by hackers, resulting in the loss of some assets,” the company wrote on X, formerly Twitter. “Deposit and withdrawal services on Mixin Network have been temporarily suspended. After discussion and consensus among all nodes, these services will be reopened once the vulnerabilities are confirmed and fixed.”
The company said it contacted Google and crypto security firm SlowMist to help with the investigation.
Mixin describes its product as an “open and transparent decentralized ledger, which is collectively booked and maintained by 35 mainnet nodes.” In other words, the Mixin Network is a decentralized exchange and cross-chain network that allows users to transfer digital assets.
“We build open source software that always puts security, privacy and decentralization first,” the company says on its website, where Mixin claims it has one million users as of July.
At this point, it’s unclear how hackers were able to steal the money after hacking into Mixin’s cloud database, given that — in theory — Mixin is decentralized.
Google spokesperson Melanie Lombardi confirmed in an email to TechCrunch that “Mandiant has been engaged by Mixin in support of the incident response.” Mandiant is a cyber incident response firm that was acquired by Google last year.
Mixin, and SlowMist did not immediately respond to a request for comment.
In the announcement, Mixin also said that it will announce an unspecified “solution” to deal with the stolen assets at a later date.
The hack on Mixin is the biggest theft in the crypto world in 2023, according to data maintained by Rekt, an organization that publishes a list of hacked crypto organizations and projects. The previous highest theft was that of Euler, a crypto lending platform, which experienced an attack that resulted in the loss of around $197 millions in March.
UPDATE, September 25, 3:46 p.m. ET: This story was updated to include comment from Google’s spokesperson.
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