Not checking answer min/max price would return the wrong price

Summary

Not checking answer min/max price would return the wrong price.

Vulnerability Detail

The getPrice() function should be checks answer is not below minPrice or not above maxPrice. but we can see there is no check: return (answer.toUint256() * Constants.PRICE_PRECISION) / 10 ** decimals; in this scenario if the price crash and drop below minPrice, aggregator still returns minPrice. It can lead to loss of funds for users.

For example:

Token minPrice is $0.5
Price drop to $0.2
Aggregator still returns $0.5

Impact

Aggregator still returns minPrice when the price is below minPrice, that's can lead to loss of funds for users because they deal with the wrong price.

Code Snippet

function getPrice(address token_) external override returns (uint256) {
        /// remap token if possible
        address token = remappedTokens[token_];
        if (token == address(0)) token = token_;

        uint256 maxDelayTime = timeGaps[token];
        if (maxDelayTime == 0) revert Errors.NO_MAX_DELAY(token_);

        /// Get token-USD price
        uint256 decimals = registry.decimals(token, USD);
        (
            uint80 roundID,
            int256 answer,
            ,
            uint256 updatedAt,
            uint80 answeredInRound
        ) = registry.latestRoundData(token, USD);
        if (updatedAt < block.timestamp - maxDelayTime)
            revert Errors.PRICE_OUTDATED(token_);
        if (answer <= 0) revert Errors.PRICE_NEGATIVE(token_);
        if (answeredInRound < roundID) revert Errors.PRICE_OUTDATED(token_);

        return
            (answer.toUint256() * Constants.PRICE_PRECISION) / 10 ** decimals;
    }

https://github.com/sherlock-audit/2023-07-blueberry/blob/7c7e1c4a8f3012d1afd2e598b656010bb9127836/blueberry-core/contracts/oracle/ChainlinkAdapterOracle.sol#L102-L126

Tool used

Manual Review

Recommendation

Consider checking the answer like this: if (answer >= maxPrice or answer <= minPrice) revert();

Duplicate of #22

sherlock-audit / 2023-07-blueberry-judging

Avci - Not checking answer min/max price would return the wrong price #69