A smartphone and a screen show the website OpenSea, where digital artworks are sold using NFT. NFTs, non-fungible tokens, are unique cryptographic credentials that are written to the blockchain attached to a file (image, music, video).A smartphone and a screen show the website OpenSea, where digital artworks are sold using NFT. NFTs, non-fungible tokens, are unique cryptographic credentials that are written to the blockchain attached to a file (image, music, video).

The company's chief executive said late Saturday that OpenSea was investigating a phish attack that no longer appeared to be active.

We don't believe it's connected to the OpenSea website. Some of the users have had their NFTs stolen, and it appears that 32 of them have signed a malicious payload from an attacker. Over the past year, NFTs have surged in popularity.

The ownership of these assets is recorded on a digital ledger similar to the networks that underpin cryptocurrencies. A person can't exchange one NFT for another as they would with dollars or other assets. Each NFT is unique and can be duplicated, making them rare.

Some of the stolen NFTs have been returned.

There were rumors that the hack was worth $200 million. The hacker has over one million dollars in his wallet from selling some of the stolen NFTs.

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