What happened
On June 8, 2026, Flooring Protocol's Ethereum fractionalized-NFT platform was exploited through a DN404/BT404-derived fpToken accounting flaw. The attack created more than $900K of temporary exposure, but a Yuga Labs-led white-hat operation rescued 68 NFTs valued at approximately $500K-$570K, leaving the protocol's net financial loss near zero.
The fpToken design maintained competing ownership and balance sources of truth: packed token-indexing logic could create a ghost-ownership state, while an integer underflow converted a dust WETH amount into a near-infinite fpToken balance. The resulting accounting was not constrained to the 1:1 locked-NFT backing invariant.
How it happened
- The attacker supplied a crafted token ID that made internal ownership bookkeeping treat unowned assets as attacker-owned, then used the underflow path to inflate fpTokens and drain fractionalized-NFT liquidity pools.
- White-hat rescuers recovered 68 affected NFTs, so the cited reports describe exposure and rescue value rather than a confirmed material final loss.
Protocol details
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