Key Takeaways:
Attackers minted roughly $49 billion face-value SAND on Base through an infinite mint exploit, executing more than 400 transactions of unbacked tokens on Aug. 21, according to security firm Blockaid.
"Attackers hijacked LayerZero delegate permissions via approveAndCall and minted unbacked SAND," Blockaid said in a post on X. The exploit targeted The Sandbox's cross-chain OFT contract on Base, bypassing the protocol's supply controls.
PeckShield identified 14.9 billion SAND across two addresses, 0xAbE0...4D22 and 0x638C...F296, nearly five times the token's 3 billion maximum supply. The Ethereum OFT adapter lost about 14.75 million SAND, worth roughly $675,000 at the time, with 79.74 ETH converted from stolen funds. The $49 billion figure represents the nominal market value of newly created tokens, not confirmed stolen assets — selling that volume would crash SAND's price.
The Sandbox confirmed the vulnerability affected its cross-chain bridge on Base and BNB Smart Chain, representing less than 0.01 percent of total supply, and has stopped bridging on both networks. Ethereum and Polygon were not affected, and no user wallets were compromised. The team is taking a pre-attack snapshot and plans to compensate eligible liquidity providers.
Bithumb suspended SAND deposits and withdrawals, while Upbit issued an investor warning over abnormal on-chain activity. CertiK also flagged the incident as the situation continued to develop.
Despite the exploit, SAND traded at $0.0476, up 4.76 percent over 24 hours, with trading volume jumping more than 400 percent. The price resilience reflects the lack of confirmed transfer trails for the newly minted supply and the relatively small share of Base-based liquidity in overall trading volume.
The incident follows the Harmony exploit that created roughly 4 billion ONE without authorization, and a WEMIX contract breach that enabled 5.23 million WEMIX$ to be minted. Each case placed control of token issuance at the center of the attack, raising broader questions about cross-chain OFT contract security across protocols using LayerZero-based infrastructure.
The Sandbox has asked users not to buy, sell, or trade SAND on Base or BSC while the team finalizes its remediation plan. The immediate risk is whether the unauthorized supply can move into bridges or decentralized exchanges with usable liquidity before the fix is fully deployed.
This article is for informational purposes only and does not constitute investment advice.
