BitBay’s Polygon DAI/USDC vault, UsdcDaiV4Vault, was exploited. The attacker first called reposition() to force the vault’s liquidity to zero, then redeemed only one minimal share. Because _withdraw() sends the contract’s entire token balance when liquidity == 0 instead of the user’s proportional share, about 14,838.47 DAI (roughly $14,000) was drained.