The `_approveCollateralTokenForAave` function use `safeIncreaseAllowance` which will not work for token like USDT
Summary
Some tokens (like USDT) have non-standard ERC20 implementations, such requiring approvals to be set to zero before changing them.
Vulnerability Details
The _approveCollateralTokenForAave function uses safeIncreaseAllowance, which may not work for these tokens. For example, if the current allowance is non-zero, safeIncreaseAllowance will revert for USDT. Thus, this function might fail for certain tokens, requiring the allowance to be reset to zero first. The correct approach would be to call safeApprove with zero first, then safeIncreaseAllowance. However, the current code uses safeIncreaseAllowance, which could revert for tokens like USDT.
Impact
Tools Used
Manual review
Recommendations
USDT requires allowance reset to 0 before using safeIncreaseAllowance
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