Upbit and Bithumb Flag The Sandbox's SAND for Unresolved Security Concerns

South Korean crypto exchanges Upbit and Bithumb have placed The Sandbox's SAND token under investment caution due to unresolved security concerns. A cross-chain bridge incident led to unbacked SAND being minted on Base and BNB Smart Chain, prompting the exchange to suspend deposits and withdrawals since August 22.

The Sandbox team has identified and contained a vulnerability affecting its SAND cross-chain bridge on Base and BNB Smart Chain. According to the project, an attacker was able to mint unbacked SAND, but the actual impact is estimated to be less than 0.01% of SAND's total supply.

Upbit will review SAND through late September, potentially removing or extending its warning, while Bithumb expects a decision on extending or removing the designation by early October. If concerns remain unresolved, Upbit may withdraw trading support for SAND.