Binance, which describes itself as the largest crypto exchange by trading volume, is the latest company to be impacted by a major theft this year.
A Binance-linked blockchain was involved in a $570 million hack late Thursday, a company spokesperson confirmed to CNN Business on Friday.
Binance temporarily suspended its blockchain network, BNB Smart Chain, “due to irregular activity,” the company tweeted Thursday. The company said Friday that hackers had stolen two million BNB cryptocurrency tokens – which are issued by Binance – worth about $570 million at the time.
Binance CEO Changpeng Zhao initially tweeted that an estimated $100 million worth of crypto had been stolen.
“Your funds are safe,” Zhao tweeted on Thursday night. “We apologize for the inconvenience.”
The company said $100 million worth of tokens remain “unrecovered” and moved off chain by the hacker. The remaining funds have been frozen on the BNB Chain.
In order to carry out the theft, the hackers targeted what’s called a cross-chain bridge. Bridges, increasingly the targets of hackers in recent months, are the infrastructure that allow users to exchange crypto assets between different blockchains.
Bridge services typically hold large reserves of various coins. These coin reserves are attracting the attention of hackers and turning blockchain bridges into prime targets for heists, according to blockchain analysis firm Elliptic.
Some $1.83 billion has been stolen from bridges as of August, with the majority of that ($1.21 billion) taking place just this year, according to Elliptic. Some of the largest thefts this year include $190 million stolen from cryptocurrency bridge provider Nomad in August, California-based firm Harmony’s $100 million loss in late June, and Axie Infinity’s Ronin bridge $625 million hack in March.
This latest attack put the BNB blockchain offline for about nine hours. In order “to stop the incident from spreading,” the chain ecosystem contacted each of the chain’s validators, who verify transactions on the blockchain as legitimate, BNB wrote in a company post.
The chain was back up and running around 2:30 a.m. ET. according to a company tweet.