What happened
A threat actor has reportedly offered a critical zero-day exploit chain targeting OpenSea for sale on underground hacking forums, with a listed price of $100,000 in cryptocurrency. The exploit allegedly targets flaws in OpenSea’s Seaport protocol order validation logic across Ethereum Mainnet, Polygon, and Blast networks, enabling attackers to force-transfer NFTs without paying any cryptocurrency. The exploit chain is described as capable of bypassing listing approvals and affecting both active and inactive listings through signature malleability and cross-collection attack techniques. The seller claimed to provide proof-of-concept code and a demonstration upon purchase, presenting it as a complete exploit chain capable of draining assets without requiring user interaction. The listing was first observed by Dark Web Informer, and as of the reporting date, OpenSea had not issued any patch or official statement, and no confirmed thefts linked to the exploit had been observed on-chain.Â
Who is affected
Users of OpenSea, particularly those holding NFTs on Ethereum Mainnet, Polygon, or Blast networks, could be affected if the exploit is legitimate, as it allegedly allows forced transfers of NFTs by exploiting Seaport protocol order validation logic.Â
Why CISOs should care
The alleged availability of a zero-day exploit chain targeting a widely used NFT platform highlights risks associated with smart contract protocols and marketplace infrastructure that manage high-value digital assets.
3 practical actions
- Monitor NFT asset activity. Review OpenSea accounts and blockchain activity for unauthorized transfers or anomalous transactions.
- Revoke unnecessary approvals. Remove unused or excessive contract permissions that could be abused if an exploit is confirmed.
- Track vendor security updates. Monitor OpenSea advisories for patches or mitigation guidance related to the Seaport protocol vulnerability.