Core Contracts

Vulnerability Details

The repayment process contains a critical mismatch between the DebtToken::burn() function return values and their handling in the LendingPool::finalizeLiquidation().

The return tuple order is inverted between scaled/unscaled amounts, leading to:

1. Incorrect Asset Transfers

   Scaled amount (protocol's internal accounting units) used instead of actual asset amount

2. Wrong Debt Balance Updates

   Scaled values treated as raw amounts, permanently corrupting user positions

3. Protocol Insolvency Risk

   Mismatch between actual assets and accounting records

Impact

1. Permanent loss of repaid funds

2. Users unable to reduce actual debt

3. Protocol accounting becomes unreliable

4. Liquidation mechanisms break completely

5. Protocol insolvency within hours of exploitation

Recommendations

Fix Return Value Handling