Decentralized cryptocurrency exchange Bancor is offline after a hacker managed to steal about $23 million in cryptocurrencies from the service.

Details on how the hack took place are scant. Bancor described it only as a “security breach” and said that “no user wallets were compromised.” In a later update, the company said it takes the incident seriously and is committing every resource to resolve the matter, bring the network back online and capture the hacker behind the attack.

Bancor deals with both cryptocurrencies and its own Bancor tokens for trades. Stolen in the hack were 24,984 in Ethereum worth $11.9 million at the time writing, 229.3 million NPXS tokens worth approximately $1 million and 3.2 million BNT tokens, Bancor’s own token, worth about $10 million at the time of the theft.

Interestingly, though the hacker stole BNT tokens, Bancor itself has built-in support to freeze funds and that’s exactly what it did with the stolen BNT tokens, meaning the net loss comes in closer to $13 million.

“We were able to freeze the stolen BNT, limiting the damage to the Bancor ecosystem from the theft,” the company said in a statement. “The ability to freeze tokens was built into the Bancor Protocol to be used in an extreme situation to recover from a security breach, allowing Bancor to effectively stop the thief from running away with the stolen tokens.”

On the theft of the other cryptocurrencies, Bancor noted that “it is not possible to freeze the ETH or any other stolen tokens. However, we are now working with dozens of cryptocurrency exchanges to trace the stolen funds and make it more difficult for the thief to liquidate them.”

Exit scams are a dime a dozen in initial coin offerings, with hacking often used as an excuse as the founders walk out the door with the tokens raised. But that doesn’t appear to be the case with Bancor at this point given that the company itself raised $153 million in its ICO in January 2017. If this were a scam, the founders wouldn’t have stuck around for 18 months and they would have stolen much larger sums of cryptocurrency.

The Bancor site remains offline as of 10:40 p.m. EDT, with the company hoping to resume its services shortly.

Image: Bancor