Upbit and Bithumb placed The Sandbox’s SAND token on their investment caution lists on Aug. 24, citing unresolved security incidents involving its wallet and distributed ledger. Deposits and withdrawals had already been suspended on both exchanges since Aug. 22. The Sandbox said a bridge vulnerability allowed unbacked SAND to be minted on Base and BNB Smart Chain, while Ethereum and Polygon balances and user wallets remained unaffected and the impact was less than 0.01% of total supply. Bithumb will decide between Sept. 28 and Oct. 2 whether to remove or extend the caution designation or terminate trading support.