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Mark Cuban loses $870,000 in crypto hack, billionaire blames bad version of MetaMask software

Role: Reporter
Marco Quiroz-Gutierrez is a reporter for Fortune covering general business news.

Mark Cuban, owner of the Dallas Mavericks, lost hundreds of thousands of dollars in a crypto scam.
Mark Cuban, owner of the Dallas Mavericks, lost hundreds of thousands of dollars in a crypto scam.
Quinn Harris—Getty Images

Even billionaire NBA owners aren’t immune from crypto exploits.

On Monday, Dallas Mavericks owner and Shark Tank investor Mark Cuban lost $870,000 worth of tokens in a crypto scam that drained one of his digital wallets. The weekend attack, first tweeted by pseudonymous Twitter user @WazzCrypto, came after 160 days of inactivity for Cuban’s wallet and drained it of 10 types of tokens, including the stablecoin USDC, Lido-staked Ether, SuperRare tokens, and Ethereum Name Service.

Cuban was alerted to the scam by crypto news outlet DL News and said the hack might have happened after he downloaded a new version of a crypto wallet.

“I’m pretty sure I downloaded a version of MetaMask with some shit in it,” Cuban told the news organization.

MetaMask is a popular self-hosted crypto wallet that can be used as an app or browser extension. It is a common ploy for crypto scammers to promote compromised versions of the software that let them access the wallet after a user downloads it.

Cuban said MetaMask crashed on his computer several times before he was alerted to the hack by DL News. He said he quickly locked his NFTs on OpenSea and transferred all the Polygon tokens he had in the hacked account. None of his other crypto wallets were reportedly affected. 

“I went on MetaMask for the first time in months. They must have been watching,” he told DL News.

Cuban has been active in the crypto space for years. In years past, he endorsed a DeFI token, Titan, which later fell apart in a crypto bank run in 2021. He was also an advocate for Voyager Digital, a crypto firm that filed for bankruptcy last year.

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